IMPROVEMENTS IN APPARATUS FOR SHARPENING VERTICAL AND CIRCULAR SAWS WITHOUT THE USE OF FILES
Year: 1864

page_text: LETTERS PATENT to Jeremiah Robinson, of 125, New Kent Road, in the
County of Surrey, Machinist, for the Invention of "IMPROVEMENTS IN
APPARATUS FOR SHARPENING VERTICAL AND CIRCULAR SAWS WITHOUT THE USE
OF FILES."
Sealed the 10th January 1865, and dated the 12th July 1864.
PROVISIONAL SPECIFICATION left by the said Jeremiah Robinson at the
Office of the Commissioners of Patents, with his Petition, on the
12th July 1864.
I, JEREMIAH ROBINSON, of 125, New Kent Road, in the County of Surrey,
5 Machinist, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN APPARATUS FOR SHARPENING VERTICAL AND CIRCULAR SAWS WITHOUT THE
USE OF FILES," to be as follows:--
This Invention relates to a machine for sharpening vertical and circular
saws by means of a small grindstone or surface which enters between the teeth
of the saw, which small revolving grinding surface receives rotary motion.
This machine is represented in the annexed Drawings, in which Fig. 1
represents the front elevation of the machine; Fig. 2 represents a side eleva-
tion of the machine, furnished with the apparatus for sharpening vertical saws;
Fig. 3, front extremity of the machine, furnished with the apparatus for
sharpening circular saws; Fig. 4, front elevation of the machine, also furnished
with the apparatus for sharpening circular saws (in this part the grinding or
sharpening surface is removed from the machine); Fig. 5, plan of cross table,

page_text: showing the quadrant for obtaining reverse angles for vertical saws; Fig. 6,
plan of table on which the apparatus for sharpening circular saws is fixed,
showing the top of slide and quadrant for obtaining the required angles. In
all these Figures similar letters of reference indicate like parts where they
recur.
z, back frame of the machine; y, front frame of the machine; x, x, stays for
holding y and z firmly together; w, table bolted to frames y and z; v, v,
uprights fixed to table w by means of bolts; u, bracket bearing fixed to the
upper part of uprights v, v, it is extended towards the front part of the
machine; t, t, swinging frame moving on two joints fixed to a moveable ring
capable of turning on a curved guide fixed to uprights v, v.
The ring r
carries two small points; for marking on au index the angle required. q,
horizontal spindle mounted on two centres at the front extremity of frame t, t;
p. substance of emery for grinding, fixed on spindle 9; this grinding surface
receives motion at the rate of five hundred revolutions per minute; its periphery,
which is shaped like the teeth of the saw, is caused to enter between each of
the consecutive teeth, and thereby effects the sharpening of the saw so far as
the gulletting of the saw is concerned. 0, 0, grooved pullies keyed on to
spindle g; they receive rotary motion from a gut driven by a strap pully n
turning in two bearings united near the bottom of levers m, which are bolted
to the top of v, v. 1, screw for the purpose of extending or tightening the gut s;
k, counterweight having a slot for the purpose of adjusting the balance of
emery wheel when required according to its thickness or diameter; the
lever j oscillates on the extremity of support ; this counterweight is intended
to maintain the equilibrium of the swinging frame t, which is supported by a
chain or spiral spring; i, i, bandles fixed to t, t, for the purpose of raising or
lowering the grinding surface; h, saddle, into which is fitted a cross slide on
which the long cross table g is fixed; g, stationary part of the cross table; it is
supported by saddle h; f, body of the sliding carriage; it slides horizontally on
the top of cross table g, and is surmounted by wooden clamps e, e, between
which the saw to be sharpened is piuched by screws; it can be moved round
horizontally to any required angle; d, small pinion in the interior of 9; it is
worked by means of a crank c; b, b, a rack fixed underneath e, e, which is
worked by turning of pinion d; a, quadrant fixed in front on to cross table 9
for the purpose of obtaining required angles for vertical saws.
The machine being mounted as indicated in the Drawings its action will be
easily understood; the workman takes hold of the handles i, i, of frame t, and
lowers it until the rotatory grinding stone or surface acts sufficiently on the
teeth of the saw, and adjusts swing frame t to the height desired by the

page_text: means of a chain or spiral spring which is attached to the hook at the front
extremity of lever j, on which the counterweight k is regulated. The sharpening
stone or surface can be readily applied to the teeth. The sliding carriage and
saw being reversed, the other side of the saw may be sharpened with equal
precision; the various angles required are indicated on the quadrant index on
each side of uprights v, v, and also on cross table g and on table w. The
grinding surface is allowed to act on the tooth until it is quite sharpened,
after which the frame t is released and carried up, thus raising the grinding
surface; the sliding carriage is then actuated by turning crank c until the
third tooth is presented to the action of the grinding surface, when it is again
lowered, and so on. Thus all odd numbers of teeth, or those set on one side,
are sharpened, after which by reversing the saw and the sliding carriage all
the even numbers of teeth, or those set on the opposite direction, can be
sharpened by the same means. e¹, e¹, band gear, which is easily thrown in or
out by a touch of the foot.
When it is desired to render this machine applicable to the sharpening of
circular saws the cross table g is removed as well as its bearings, and replaced
by a special carriage, represented at Figs. 3 and 4, seen in front and side views.
b', bearing bolted to frame y, thus providing ample space for a large saw of
six feet diameter, part of which saw may be lowered through the floor as far
as necessary, and sharpened as readily as one of smaller diameter; d', upright,
the lower extremity of which rests on bearing b' to which it is bolted so as not
to remove from any fixed angle; at its upper extremity a small plate is bolted,
and can be removed inward or outward by the use of the slider (according to
the reduction in diameter of the emery wheel), which plate being set to a
required angle is made secure by being bolted to bench w; this horizontal
circular motion of the apparatus is intended to effect the same purpose as that
of carriage f; v, v', cross beam furnished with a fillet, which always maintains
the cross beam in a horizontal position therein; A, A, groove, made nearly
throughout the length of cross beam v¹; a collar is provided to fit the spindle
hole of the circular saw, which is fixed on cross beam v³, and traverses along
the slot c', and is made secure by the use of a nut which holds the upright d¹
in its required position. When it is desired to sharpen the top part of each
tooth then the emery wheel which has been used for the purpose of gulletting
is removed from swing frame t, and another emery wheel having a flat edge
is fixed in its place and lowered on to the top of each consecutive tooth by
taking hold of handles i, i, until the teeth are sufficiently sharpened, and the
swing frame t and emery wheel are reversed, as also the carriage e, e, and saw
also, in order to sharpen the teeth set on the other side.

page_text: are claimed by me are,-
1st, the use of the moveable counterweight k on the lever j.
2nd, in the application of the quadrant a to the cross table g for the
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Jeremiah Robinson in the Great Seal Patent Office on the
12th January 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JEREMIAH
ROBINSON, of 125, New Kent Road, in the County of Surrey, Machinist,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twelfth day of July, in the year of our Lord
One thousand eight hundred and sixty-four, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Jeremiah Robinson, Her special licence that I, the said Jeremiah
Robinson, my executors, administrators, and assigns, and such others as
I, the said Jeremiah Robinson, 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 law-
fully 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 SHARPENING VERTICAL AND
CIRCULAR SAWS WITHOUT THE USE OF FILES," upon the condition (amongst
others) that I, the said Jeremiah Robinson, my executors or administrators,
by an instrument in writing under my, or their, or one of 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 Jeremiah Robinson, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the Sheet of Drawings hereunto annexed,
and to the letters and figures marked thereon (that is to say) :-
:-
This Invention relates to a machine for sharpening vertical and circular

page_text: saws without the use of files by means of a small emery wheel or surface
which enters between the teeth of the saw, which small revolving grinding
surface receives rotary motion.
This machine is represented in the annexed Drawings, in which Fig. 1
represents the front elevation of the machine; Fig. 2 represents a side eleva-
tion of the machine, furnished with the apparatus for sharpening vertical
saws; Fig. 3, front extremity of the machine, furnished with the apparatus
for sharpening circular saws; Fig. 4, front elevation of the machine, also
furnished with the apparatus for. sharpening circular saws (in this part the
grinding or sharpening surface is removed from the machine); Fig. 5, plan of
quadrant on the cross table for obtaining required angles; Fig. 6, plan of table
on which the circular saw is fixed, showing the slide and quadrant for
obtaining required angles for circular saws. In all these Figures similar
letters of reference indicate like parts where they recur.
z, back frame of the machine, fixed to the ground by means of bolts; y,
front frame of the machine, also fixed to the ground by bolts; x, x, stays for
holding y and z firmly together; w, table bolted to frames y and z; v, v,
uprights fixed to table w by means of bolts; u, bracket bearing fixed to
the upper part of uprights v, v; it is extended towards the front part of
the machine; t, t, swinging frame moving on two joints fixed to a movable
ring capable of turning on a curved guide fixed to uprights v, v. The fixing
of the ring and guide is effected by means of bolts, as seen in Fig. 4. The
ring r carries two small points for marking on an index the angle required.
q, horizontal spindle mounted on two centres at the front extremity of frame t, t;
p, substance of emery for grinding, fixed on spindle q; this grinding surface
receives motion at the rate of, say, five or six hundred revolutions
per minute
its periphery, which is shaped like the teeth of the saw, is caused to enter
between each of the consecutive teeth, and thereby effects the sharpening of
the saw so far as the gulletting is concerned. 0, 0, grooved pullies keyed on
to spindle g; they receive rotary motion from gut 8, driven by strap pully n
turning in two bearings united near to the bottom of levers m, which are
bolted to the top of v, v. 1, screw for extending and tightening the guts;
k, counterweight with a slot for the purpose of adjusting the balance of emery
wheel when required according to its weight, the lever of which oscillates on
the extremity of support u; this counterweight is intended to maintain the
equilibrium of the swinging frame t, which is supported by a chain which is
attached to the hook at the front extremity of lever j, on which the counter-
weight k is regulated; i, i, handles, fixed to t, t, for the purpose of raising or
lowering the grinding surface; h, saddle, into which is fitted a cross slide on

page_text: which the long cross table g is fixed; g, stationary part of the cross table; it is
supported by saddle h; f, body of the sliding carriage; it slides horizontally on
the top of cross table g, and is surmounted by wooden clamps e, e, between
which the saw to be sharpened is pinched by screws; it can be moved round
horizontally to any required angle to the one side or to the other; d, small
pinion in the interior of cross table g; it is worked by hand by means of a
wheel c, which being turned causes the rack 6, b, and sliding carriage f to
move horizontally either to the right or to the left. This movement of the
sliding carriage, and consequently of the saw, serves to conduct each tooth
successively before the sharpening grinding instrument or surface.
The machine being mounted as indicated in the Drawings its action will be
readily understood. Supposing, 1st, that pulley n receives rotary motion from
any motor, this motion will be transmitted by means of gut band s to spindle q,
which supports the grindstone p; 2ndly, that the saw to be sharpened has
been pinched between the clamps e, e, of the sliding carriage f. In order to
sharpen the saw the workman takes hold of the handle i, i, of swing frame t,
and lowers it until the rotatory grinding surface acts sufficiently in the tooth
of the saw, and then adjusts the swing frame t at its desired height by means
of the chain attaching it to the lever j. The "lead" (or angle crosswise) of
every consecutive. tooth is secured by the use of quadrant a on the front of
cross table g; the saw being inclined, as also the clamps and cross table, the
swing frame and consequently the grindstone can be suitably inclined. The
different "hold and lead" which the swing frame and grinding surface may be
made to produce is indicated by an index on each side of uprights v, v, and
quadrant a on cross table g. The grinding surface is allowed to act on the
tooth until it is sharpened, after which the frame t is released and carried up
by the counterweight, thus raising the grinding surface; the sliding carriage
is then actuated by turning wheel c until the third tooth is presented to the
action of the grinding surface, when it is again lowered and so on.
When it is desired to render this machine applicable to the sharpening of
circular saws, the fixed carriage and cross table are removed as well as their
bearings, and a special carriage substituted for them, represented in Figs. 3 and
4, seen in front and side views. 61, bearing bolted to frame y, thus providing
ample space for a large saw of six feet diameter, part of which saw may be
lowered through the floor as far as necessary, and sharpened as readily as one
of smaller diameter; d', upright, the lower extremity of which rests on bearing
6', to which it is bolted; at its upper extremity a small plate is bolted having
a quadrant for obtaining the required "lead" or angle, and can be removed
inward or outward by the use of the slide plate 2 (according to the reduction
202

page_text: in diameter of the emery wheel), which plate being set to a required angle is
made secure by being bolted to bench w; this horizontal circular motion of
the apparatus is intended to effect the same purpose as that of carriage f;
v, v', cross beam furnished with a fillet, which always maintains the cross
beam in a horizontal position therein; A, A, groove made nearly throughout
the length of cross beam v¹; a collar is provided to fit the spindle hole of
the saw, which is fixed on cross beam v³, and traverses along the slot c', and
is made secure by the use of a nut which holds the upright d' in its required
position. When it is desired to sharpen the top part of each tooth then the
emery wheel which has been used for the purpose of gulletting is removed from
swing frame t, and another emery wheel having a flat (or square edge) is
fixed in its place, and lowered on to the top of each consecutive tooth by
taking hold of handles i, i, until the teeth are sufficiently sharpened, then the
swing t frame and emery wheel are reversed, as also the cross table g and
sliding carriage f and saw also, in order to sharpen the teeth set on the other
side, thus entirely dispensing with the use of files. The action of this machine
is the same for circular saws as for straight ones, and produces the desired
effect in a perfect manner.
In witness whereof, I, the said Jeremiah Robinson, have hereunto set
my hand and seal, the Twenty-ninth day of December, in the year
of our Lord One thousand eight hundred and sixty-four.
Witness,
J. H. BROWN,
207, Southgate Road,
London.
JEREMIAH ROBINSON. (L.B.)