IMPROVED MACHINERY FOR SHAPING AND SHARPENING SAWS
Year: 1864

page_text: LETTERS PATENT to Edward Joseph William Parnacott, of Leeds, in the
County of York, Mill Sawyer, for the Invention of "IMPROVED MACHINERY
FOR SHAPING AND SHARPENING SAWS."
Sealed the 4th April 1865, and dated the 10th November 1864.
PROVISIONAL SPECIFICATION left by the said Edward Joseph William
Parnacott at the Office of the Commissioners of Patents, with his
Petition, on the 10th November 1864.
I, EDWARD JOSEPH WILLIAM PARNACOTT, of Leeds, in the County of York,
Mill Sawyer, do hereby declare the nature of the said Invention for "IM-
PROVED MACHINERY FOR SHAPING AND SHARPENING SAWS," to be as follows:-
This Invention relates to a novel arrangement of machinery for shaping
and sharpening the teeth of saws by the aid of emery wheels or other rotary
cutters, the object being to complete the sharpening of saws generally by
machinery. To this end I fix the saw (whether it be a straight saw or a
circular) in a compound clamp, which slides in grooves upon a horizontal
table, to which it is capable of being fixed securely for the purpose of presenting
the saw to the rotary cutter. The clamp also admits of being turned on a
fulcrum bolt to incline the edge of the straight saw to the axis of the cutter.
The straight or blade saw is traversed longitudinally past the cutter by means
of a hand wheel working a pinion and rack with which the compound clamp
'is fitted. The horizontal table is made capable of adjustment vertically, in
order to tip the saw and raise one end or edge thereof, while the other is

page_text: correspondingly depressed. The cutter is mounted in a vibrating frame carried
by a horizontal turn plate, and its forward movement to reach its work is
-adjusted by a fixed stop, so that a uniform depth of tooth is ensured. A
vertical movement is given to the cutter by means of a screw and hand wheel,
which raise and lower the bracket that carries the turn plate. This vertical
adjustment determines the angle at which the periphery of the cutter will act
upon the saw.
Motion is communicated to the cutter in the following manner :-A band
passing from a pulley on the driving shaft gives motion to a double groove
pulley mounted on a sliding headstock. A band from this pulley passes round
a pulley keyed on the fulcrum shaft of the cutter frame, and transmits motion
thereto. To the fulcrum shaft are also keyed speed pullies, and on the axle
of the cutter is fixed a driving pulley. This latter pulley is driven by a strap
from one of the speed pullies, and thus the vibration of the cutter frame in no
way affects the driving of the cutter.
The chief advantages of this over the old arrangement are, that'a bevil can
be given to the gullet of the tooth, and that the cutter is enabled to top or
finish the teeth, both at the front and back of the teeth, and to any bevil that
may be required; the sharpening of gullet or briar teeth, and the topping or
finishing of them being effected as readily as the sharpening and finishing of
any other form of teeth.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Joseph William Parnacott in the Great Seal Patent
Office on the 10th May 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I,. EDWARD
JOSEPH WILLIAM PARNACOTT, of Leeds, in the County of York, Mill Sawyer,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Tenth day of November, in the year of our
Lord One thousand eight hundred and sixty-four, in the twenty-eighth year
of Her reign, did, for Herself, Her heirs and successors, give and grant.
unto me, the said Edward Joseph William Parnacott, Her special licence
that I, the said Edward Joseph William Parnacott, my executors, adminis-
trators, and assigns, or such others as I, the said Edward Joseph William
Parnacott, my executors, administrators, and assigns, should at any time
agree with, and no others, from time to time and at all times thereafter

page_text: 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 "IM-
PROVED MACHINERY FOR SHAPING AND SHARPENING SAws," upon the condition
(amongst others) that I, the said Edward Joseph William Parnacott, 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 Edward Joseph William Parnacott, 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 Drawings hereunto
annexed, and to the letters and figures marked thereon (that is to say) :-
This Invention relates to a novel arrangement of machinery for shaping and
sharpening the teeth of saws by the aid of emery wheels or other rotary cutters,
the object being to complete the sharpening of saws generally by machinery.
In order to attain this end I provide for the relative adjustment of the saw
(whether it be a straight saw or a circular) and the emery wheel or cutter, so
that all the cuts required to complete the saw sharpening operation may be
given by the machine instead of relying as heretofore on finishing by hand
the more complex forms of teeth.
Most of the details of my improved machine will be familiar to those who
are acquainted with the machine which forms the subject of a Patent granted
to William Clark, dated November First, One thousand eight hundred and
fifty-eight, as a communication from abroad, and it is to remedy the defects of
that machine, as respects its incompetency to finish gullet teeth that I have
designed the machine which I will now describe. The saw blade is held in
a compound clamp, which slides upon a horizontal table, to which it is capable
of being fixed securely for the purpose of presenting the saw to the rotary
cutter. This table is mounted on pins, which allow of its being rocked from
side to side, in order that the saw blade may be raised at one end and
depressed at the other to suit the angle of cut to be given to the saw teeth.
The straight or blade saw is traversed longitudinally past the cutter by means
of a hand wheel working a pinion and rack with which the compound clamp
is fitted. The cutter is mounted in a vibrating frame carried by a horizontal
turn plate, and its forward movement to reach its work is adjusted by a fixed

page_text: stop, so that a uniform depth of tooth is ensured. A vertical movement is
given to the cutter by means of a screw and band wheel, which raise and
lower the bracket that carries the turnplate. This vertical adjustment
determines the angle at which the periphery of the cutter will act upon the
saw, and it thus enables the cutter to make a square or a chamfer cut as
desired.
In Sheet I. of the accompanying Drawings, Fig. 1 is a front elevation of the
improved saw-sharpening machine; Fig. 2 is a side elevation of the same,
partly in section; Fig. 3 is a back elevation, shewing the standard table and
driving gear; Fig. 4 is a partial sectional plan, shewing the turntable which
carries the cutter frame, and Fig. 5 is a plan view of the clamp for holding a
blade or web saw, and presenting it to the emery wheel, and Fig. 6 is a
partial plan view of the table detached.
In Sheet II., Fig. 7 shews in side elevation the table fitted with a clamp
for holding a circular saw, and presenting it to the action of the
emery wheel
or cutter; Fig. 8 is an end view of the slotted table, shewing the bolt and
socket for holding the circular saw, and Fig. 9 is a plan view, shewing the
circular saw under the action of the cutting wheel.
In Sheet I., A, A, is a hollow cast-iron standard, which carries at its upper
end the rocking table, and is further provided with adjustable and fixed
brackets for carrying the various working parts of the machine. B is the
driving shaft mounted in two journals fixed on the bottom flange of the hollow
standard A, A. This shaft carries the fast and loose belt pullies C, C, and
also a grooved driving pulley C', which transmits rotary motion through a
band to a grooved pulley Ex on the end of a short shaft E, carried by a head-
stock E. This headstock slides upon a bracket D projecting from the back
of the standard A. Upon the fixed bracket is mounted a weighted crank
lever Es, which by pressing against an adjusting screw E³ connected with the
headstock keeps the endless driving band, which gives motion to the cutting
wheel at the proper tension. The short shaft E, which is mounted in journals
in the headstock E¹ carries two grooved pullies F, F, for the purpose to be
presently explained.
.
On the front face of the hollow standard A is a bracket G. This bracket
slides vertically on the face of the standard, and is supported by a vertical
screw H, which passes through a nut I provided with a rim, and resting upon
the bottom flange of the hollow casting, so as to be easily turned round. The
bracket is held in its proper position by a bolt (see Fig. 2) fitting into a slot
in the standard A. Upon the bracket G is fitted the turntable J, J, in which
are cast segment slots for receiving bolts, which by means of thumb nuts hold

page_text: it firmly to the bracket. In suitable brackets forming part of this turntable
are mounted the shafts K, K, Fig. 4, to each of which is keyed a guide
pulley K¹, K.
On two other projections from the turntable J, is mounted the rocking
frame L, which carries at its upper end the cutter shaft L' with its driving
pulley and emery wheel or other cutter; L² is an endless driving band, which
passing round one of the pulleys F to and under the guide pulleys K', and
thence over the grooved pulley of the cutting wheel communicates motion to
the cutting wheel, and enables that wheel when brought into contact with the
saw to sharpen the teeth thereof; the periphery of the cutting wheel being
made to correspond to the nature of the work to be performed.
This arrangement of driving gear prevents the vibration of the cutter frame
affecting in any way the driving of the cutting wheel. On the top of the
hollow standard A is mounted the rocking table M, which is carried by the
bolts M', M'. A segmental slot is made in the front end of the table to
receive a bolt M² for holding the table at any required, angle. Upon this
rocking table M is bolted the compound clamp, by which the blade or web
saw is presented to the cutting wheel. This compound clamp consists of an
adjustable standard O, which is attached securely to the table by a nut screwed
on to a clamping bolt, the head of which is shaped to slide in the longitudinal
groove formed in the face of the table, as shewn at Fig. 3. On the front face
of this standard is an L-shaped slide 0', which moves over and is supported by
L-shaped guides. The horizontal portion of this slide 0¹ forms the under jaw
of a clamp, in which the saw blade to be sharpened is placed. Over this jaw
is placed a loose jaw O³, which when the blade is in place, as shewn at Fig. 2,
is screwed down by bolts and thumb nuts, as shewn best in the plan view,
Fig. 5. Affixed at the back of the slide O is a rack 1, into the teeth of
which a pinion 2 takes. This pinion is keyed to a short axle supported in the
standard O, and carrying at its upper end a hand wheel. By simply turning
this hand wheel a traverse motion is given to the clamp, and thus the teeth
of the saw are each in succession brought under the action of the emery or
other cutting wheel.
The cutting wheels which I prefer to employ for this purpose are those made
according to my Patent bearing date the Twenty-seventh of April, One thousand.
eight hundred and sixty-four; but it will be obvious that any other suitable
rotary cutter may be adapted to my improved machine.
I may here remark that adjustable stops may be provided on the turntable
for limiting the amount of vibration of the cutter frame L, both towards and
from the work. A tendency is given to the cutting wheel to leave the work

page_text: by weighting the cutter frame at its lower end, as shewn at Figures 1 and 2 ;
and handles are provided at the upper end of the frame to enable the attendant
to bring up the wheel to its work. By means of an adjustable stop it will be
obvious that the depth of cut may be accurately determined. I have said that
the endless driving band is kept at tension by means of the weighted crank
lever E. This crank lever is forked at one end (as shewn in the detached
views Figs. 5*, which represent it in partial side and edge views) and it
embraces a collar fitted with pins, which take into slots in the fork. Into the
collar fits the end of the screw E³, which rests in a bearing in the bracket D,
and which passes through a tapped lug pendent from the head stock E'. When
therefore, by reason of the slackness of the endless band the weighted limb of
the crank lever drops out of the horizontal line, it may be brought up to its
most efficient position by turning the adjusting screw, and thrusting back the
upper limb of the crank lever.
.
From the foregoing description it will now be understood that the machine
admits, first, of the saw blade being presented to the cutting wheel at any
desired angle from a horizontal line in order to form an inclined cut; second,
besides the depth of cut being variable as desired, that any amount of chamfer
or undercut may be given to the tooth by simply raising or lowering the cutting
wheel frame; and, third, that from the cutter frame being mounted on a rising
and falling turntable, the angle of the chamfer cut may be adjusted to suit any
inclination of gullet tooth. These various movements I find essential to a
machine designed to finish the sharpening of the various kinds of saws now
used in the cutting of timber.
When it is required to sharpen circular saws by my improved machine, I
remove the slide O, and substitute for it the arrangement shewn in Sheet II. at
Figures 7 and 8. The bolt N is somewhat similar to that which slides in the
groove of the table M, and secures the slide O (Fig. 2) firmly thereto; but
in this case the bolt is provided with suitable socket and nut for gripping
the saw, in addition to the clamping nut, which secures the bolt in position on
the table, which position is determined according to the diameter of the saw
to be sharpened. A rest P is provided at the front end of the table for the
circular saw, in order to prevent its vibrating under the action of the cutting
wheel.
In order to ensure the proper step-by-step motion of the saw (whether
straight or circular) past the cutting wheel, I may adopt any of the contrivances
now in use for insuring regularity of feed, but as they form no part of my In-
vention I have not thought it necessary to enter into the details of these
contrivances.

page_text: In conclusion I would remark that the chief advantages of my improved
machine over the old arrangement are, that a bevil can be given to the gullet
of the tooth, and that the cutter is enabled to top or finish the teeth, both at
the front and back of the teeth, and to any bevil that may be required, the
sharpening of gullet or briar teeth, and the topping or finishing of them
being effected as readily as the sharpening and finishing of any other form
of teeth.
Having now set forth the nature of my Invention of "Improved Machinery
for Shaping and Sharpening Saws," and explained the manner of carrying the
same into effect, I wish it to be understood that under the above in part
recited Letters Patent I claim, the arrangement of saw-sharpening machinery
above described, whereby I am enabled to finish or carry to completion the
sharpening of gullet and other saw teeth, without the use of files or hand
labour.
In witness whereof, I, the said Edward Joseph William Parnacott, have
hereunto set my hand and seal, the Eighth day of May, in the year
of our Lord One thousand eight hundred and sixty-five.