IMPROVEMENTS IN CUTTING FILES AND RASPS, AND IN THE MACHINERY TO BE EMPLOYED THEREIN
Year: 1869

page_text: LETTERS PATENT to William Furness, of New Street, Borough Road,
in the County of Surrey, for the Invention of "IMPROVEMENTS IN
CUTTING FILES AND RASPS, AND IN THE MACHINERY TO BE EMPLOYED
THEREIN."
Sealed the 18th January 1870, and dated the 19th July 1869.
PROVISIONAL SPECIFICATION left by the said William Furness at
the Office of the Commissioners of Patents, with his Petition, on
the 19th July 1869,
I, WILLIAM FURNESS, of New Street, Borough Road, in the County
5 of Surrey, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN CUTTING FILES AND RASPS, AND IN THE MACHINERY TO BE
EMPLOYED THEREIN," to be as follows:-
The object of this Invention is to produce a file with a stronger or
more durable overcut than is ordinarily made, presenting a more square

page_text: and strong tooth, the up cut being completely driven through the over
cut, whereby the teeth are throughout the length of the file equal
proportionately in depth, thus forming a stiffer and sharper tooth.
These results are accomplished by fixing the file blank on a stationary
anvil, whereby the file blank cannot retreat from the blows of the
hammer, and by causing the hammer and cutting tool or chisel to travel
along and over the file blank. The anvil bed, which is formed of cast
iron, is let into a stone or other block to serve as a foundation for the
entire structure. The upper sides or edges of the anvil bed are planed
or cut to form the bearings of tenon or dovetail slides, on which a sliding
bed traverses to and fro longitudinally, such bed serving to carry all
portions of the machine which are moveable. In the centre of the anvil
bed the anvil for the file is formed in the solid casting, and on this the
file blank is placed, resting on a leaden plate, and held by a tang holder
and by plain studs and set screws; the anvil bed is so formed that at one
end (say the chisel holder end) it is cast with a projecting bracket for
the purpose of supporting the full length of the sliding bed; the other
end is formed with an elongated tail piece, serving also to support and
keep firm the sliding bed, and likewise to contain a rack or endless screw
or other equivalent for the purpose of actuating the feed as hereafter
described. The rack may be composed either of one, two, or more
divisions, in which latter case the scries should be arranged in parallel
lines, but in advance of each other, so that the pinion gearing therein
being also formed to correspond with such teeth, the slighest motion
of the compound pinion shall be communicated to a travelling rest or
bed, which result could not so completely be given if one series of teeth
only were formed in the rack and pinion. The sliding rest or bed is
bolted (or otherwise fixed) to two under side bars, whose internal faces
are formed to suit the angular surfaces of the anvil bed, the under
surface of the rest bearing on the upper surface of the anvil bed. This
rest carries four steps or rigid bearings which support the cross bed of
the hammer apparatus, and, through this cross bed the driving shaft
which actuates the entire machine is set in bearings at each end of the
cross. bed. The cross bed is formed with a central space or slot for the
purpose of enabling the hammer base resting on the cross bed to travel
from one side to the other of the rest (as hereafter described); this travel
is effected by loosening the screws of the base, and shifting it to the
desired position. Assuming this base to be a disc or circulár plate, a

page_text: moveable disc or corresponding plate is set thereon, provided with
circular slots in which set screws are inserted for the purpose of changing
the angle of the hammer structure which is fixed on the moveable or
turning disc, and which consists of two vertical plates bolted or fixed to
the moveable disc, and within which plates the hammer and its working
is contained. The driving shaft is cut with a feather groove or key way
and carries a vertical bevel wheel, so that the bevel wheel may follow all
positions of the hammer rest or base. This bevel gears with a horizontal
bevel undorneath the base, from which a vertical shaft extends, carrying
a second horizontal bevel communicating with a second vertical bevel
within the plates, giving its motion by a shaft passing through one plate
to a corresponding bevel outside the plate. This gives motion to a pair
of bevel wheels by means of an oblique shaft set in outside bearings, and
then to a final vertical bevel at the top of the plate, carrying the cam
shaft set in bearings through each plate, and also the cam. In the upper
part of the plates a shaft is set which forms the main fulcrum of the
hammer apparatus; this shaft carries a forked rocking shaft or bell-crank
lever, the lower extremities of which contain the bearing for the elbow
of the hammer arm; the rear of the upper part of the rocking shaft or
shoulder piece carries a roller on which the cam or volute acts at each
revolution of the shaft. The elbow lever is then joined to a connecting
link set on a fixed fulcrum across the rear of the plates, and the arm
itself extends forward to the artificial wrist joint, in which a bearing is
made for a pin to work loosely, but to which is fixed the hammer head
and two side levers for the. purpose of regulating the position or tilt of
the hammer to suit the bevel of the chisel head. This regulation is
effected by means of a vertical slot cut on each side of the front portion
of the vertical plates, and by two vertical or oblique moving links set on
a shaft passing through the slots, such links being jointed to the hori-
zontal fixed links or cranks in common with the pin and hammer head.
The shaft is raised and lowered by a horizontal hand screw motion at the
top of the plates, and gearing with the shaft or its accessories. The
object of these arrangements in regard to the hammer is to effect by
artificial means the exact motion of the human arm, so as to bring the
hammer head square or in line with the chisel. In order to increase or
decrease the intensity or power of the blow of the hammer according to
the position of the file blank to be cut, I apply a spring or india-rubber
cord or other elastic fabric behind and attached to the shoulder piece,

page_text: and by tightening or slackening this spring by means of a wheel and
screw the object is effected. At the instant the blow is struck a buffer
or cam motion applied to the elbow joint by means of a back stem, disc,
and india-rubber, or other equivalent serves to catch the recoil of the
hammer, and prevent any tremor on the chisel head. In order to raise
the hammer head clear of the chisel while the machine is at rest, or
whenever necessary, a crank handle is attached to the main shaft or
fulcrum of the hammer arm on the outside plate opposite to that con-
taining the driving pinions; this crank traverses a quadrant bar, and is
fixed thereon by means of a spring catch or pin, so as to elevate and set
the hammer as may be desired.
I now proceed 'to describe the arrangements appertaining to the chisel
and chisel holder :-On each side of the sliding bed plate a vertical or
oblique rocking arm is sét on a pivot, and carries a horizontal bar
extending towards the front of the machine, and between these bars a
transverse bar is fixed, so that the whole oscillates to and fro as one
piece (as hereafter described). On this transverse bar the arm of the
chisel holder is borne; the arm consists of a strong bracket piece cut
through to fit the transverse bar, to which it is secured by a screw and nut,
and a sliding or tightening strip, thus allowing it to be shifted on the
bar to any required position to suit the position of the hammer and file,
which is accomplished by a hand wheel and screw set in a bearing on
the transverse bar; the arm terminates by a jointed face or flange from
which a lever is extended vertically, and to the top of which a screw
working in a female socket on the bracket is connected, whereby an up
or back action or tilt is given to the chisel holder by aid of a worm
wheel working in outer teeth of the socket. To this arm 'the holder of
the chisel is bolted or otherwise secured, the holder consisting of a
socket and flange in which the ring containing the chisel is borne, the
ring being secured in the socket 'by tightening screws or pins, or both,
which serve to maintain the position or angle of the chisel corresponding
to that of the hammer. On the side of the machine opposite to that
containing the driving action the feed motion to the slide rest, hammer,
and chisel are given, as well as the lifting motion for the chisel. Now
the rocking arın on this side of the machine is made of sufficient length
to descend some distance below the sliding bed, and attached to its lower
extremity is a connecting rod actuated from an excentric which is set on

page_text: a shaft between two brackets underneath the main driving shaft, which
shaft carries a pinion working under the sliding plate at the end of the
open space; this pinion gears with an under pinion on the excentric
shaft, and thus the rocking motion is given through the excentric and
connecting rod direct to the oscillating arms by which the transverse
bar carrying the chisel holder is controlled. Outside the external
bracket carrying this last arrangement the shaft is continued, and also,
carries a second excentric and connecting rod extending obliquely down-
wards and towards the rear of the machine; this rod is then connected to.
an ascending lever and disc rocking on an axis. in line with the excentric,.
such axis being borne by a transverse bracketed bearing bolted to the
sliding rest or bed; the disc carries a ratchet pall which gears into the
teeth of a wheel set and fixed on the axis close to the loose disc, and
a spring catch pall is arranged on the other side of the toothed wheel,
so that at each revolution of the machine the wheel is moved onę
or more teeth as required. This axis or shaft held by the external;
bracket as above passes through bearings in the sliding bed, and
serves to communicate the entire feed motion to the sliding bed by
means of the pinion formerly described gearing with the fixed rack
on the anvil.
From the foregoing description the unison of the machine will be
comprehended. A fast and loose pulley being placed on the main
driving shaft, power is communicated by a driving strap from an
engine, the various bevels and the hammer action being so arranged
that the hammer shall descend on the chisel immediately the lifting:
apparatus has been drawn out of action, so as to enable the chisel
to rest on the surface of the file blank; the cam or volute on the driving
shaft of the hammer arrangement raises and releases the hammer at the
exact moment for the blow; then the lifting, excentric, and feed motions
act, and the slide bed and all the working parts are drawn simultaneously
rearwards to the exact distance for the next tooth to be cut, again the
chisel descends, and again the hammer strikes its blows. On starting
the machine the corner of the file at its point is first cut, and since this
portion of the file is thinner, and the width of the tooth to be cut is less
than in any other part, it follows that the blow of the hammer should be
proportional to the work, therefore the india-rubber or other springs
attached to the elbow movement are slackened, and consequently the

page_text: blow of the hammer is decreased; the chisel holder is drawn on the slide
so as to bring the centre of the chisel over the centre of the width of the
cut; this is effected by the hand wheel and screw on the transverse bar
of the chisel holder, and therefore as the file blank is travelled over the
chisel is shifted further over it, and the hammer is made to strike harder until
the chisel is fairly at work, or the cut set in the blank; the file blank is
kept firmly down on its bed by a pressing roller set in an arm attached
to a transverse shaft working in the steps of the slide rest, a crank or
lever being attached to it and connected to a spring, a powerful leverage
is given to the roller, which travels along the file in common with all the
inoving parts; it can be released directly the file is cut. The angle of
the chisel can be arranged so as to over cut and up cut by fixing the
transverse bar in corresponding diagonal bearings; then, as before stated,
the hammer seat or bed is to be moved across the transverse slotted rest,
and turned as a turntable so as to throw the hammer to the corre
sponding angle of the chisel; but in practice where several machines
would be in work it will be found preferable that some should be set for
the over cut and others for the up out, as required, to save the necessity
of altering the transverse bar as well as the hammer and chisel.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Furness in the Great Seal Patent Office on
the 19th January 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
FURNESS, of New Street, Borough Road, in the County of Surrey, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of July, in the year of our
Lord One thousand eight hundred and sixty-nine, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors, give and
grant unto me, the said William Furness, Her special licence that I, the
said William Furness, my executors, administrators, and assigns, or such
others as I; the said William Furness, 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,

page_text: 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 CUTTING FILES AND
RASPS, AND IN THE MACHINERY TO BE EMPLOYED THEREIN," upon the condition
(amongst others) that I, the said William Furness, 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 William Furness, 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:-
This Invention relates to certain improvements in the cutting of files
and rasps, and in the machinery whereby such cutting is effected.
The object being to produce a file with a stronger or more durable
over cut than is ordinarily made, presenting a more square and
strong tooth, the up cut being completely driven through the over cut,
whereby the teeth are throughout the length of the file equal pro-
portionately in depth, thus forming a stiffer and sharper tooth. These
results are accomplished by fixing the file blank on a stationary anvil,
whereby the file blank cannot retreat from the blows of the hammer,
and by causing the hammer and cutting tool or chisel to travel along
and over the file blank. The anvil bed which is formed of cast iron is
let into a stone or other block to serve as a foundation for the entire
structure. The upper sides or edges of the anvil bed are planed or cut
to form the bearings of tenon or dovetail slides, on which a sliding bed
traverses to and fro longitudinally, such bed serving to carry all portions
of the machine which are moveable. In the centre of the anvil bed the
anvil for the file is formed in the solid casting, and on this the file blank
is placed, resting on a leaden plate and held by a tang holder and by
plain studs and set screws; the anvil bed is so formed that at one end
(say the chisel holder end) it is cast with a projecting bracket for the
purpose of supporting the full length of the sliding bed; the other end
is formed with an elongated tail piece serving also to support and keep

page_text: firm the sliding bed, and likewise to contain a rack or endless screw, or
other equivalent, for the purpose of actuating the feed as hereafter
described. The rack may be composed either of one, two, or more rows
of teeth, in which latter case the series should be arranged in parallel
lines, but in advance of each other, so that the pinion gearing therein
being also formed to correspond with such teeth, the slightest motion
of the compound pinion shall be communicated to the travelling rest
or bed which result could not so completely be given if one series of
teeth only were formed in the rack and pinion. The sliding rest or
bed is bolted (or otherwise fixed) to two under side bars whose internal
faces are formed to suit the angular surfaces of the anvil bed, the under
surface of the rest bearing on the upper surface of the anvil bed. This
rest carries four steps or rigid bearings which support the cross bed of
the hammer apparatus, and through this cross bed the driving shaft
which actuates the entire machine is set in bearings at each end of the
cross bed. The cross bed is formed with a central space or slot for the
purpose of enabling the hammer base resting on the cross bed to travel
from one side to the other of the rest (as hereafter described); this travel
is effected by loosening the screws of the base and shifting it to the
desired position. Assuming this base to be a disc or circular plate, a
moveable disc or corresponding plate is set thereon, provided with
circular slots in which set screws are inserted for the purpose of
changing the angle of the hammer structure which is fixed on the
moveable or turning disc, and which consists of two vertical plates
bolted or fixed to the moveable disc, and within which plates the
hammer and its working is contained. The driving shaft is cut with
a feather groove or key way, and carries a vertical bevel wheel, so that
the bevel wheel may follow all positions of the hammer rest or base.
This bevel gears with a horizontal bevel underneath the base, from
which a vertical shaft extends, carrying a second horizontal bevel com-
municating with a second vertical bevel within the plates, giving its
motion by a shaft passing through one plate to a corresponding bevel
outside the plate. This gives motion to a pair of bevel wheels by means
of an oblique shaft set in outside bearings, and then to a final vertical
bevel at the top of the plate, carrying the cam shaft set in bearings
through each plate, and also the cam. In the upper part of the plates a
shaft is set which forms the main fulcrum of the hammer apparatus; this
shaft carries a forked rocking shaft or bell-crank lever, the lower extremities

page_text: of which contain the bearing for the elbow of the hammer arm; the rear
of the upper part of the rocking shaft or shoulder piece carries a roller
on which the cam or volute acts at each revolution of the shaft. The
elbow lever is then joined to a connecting link set on a fixed fulcrum
across the rear of the plates, and the arm itself extends forward to the
artificial wrist joint, in which a bearing is made for a pin to work
loosely, but to which is fixed the hammer head and two side levers for
the purpose of regulating the position or tilt of the hammer to suit the
bevel of the chisel head. This regulation is effected by means of a
vertical slot cut on each side of the front portion of the vertical plates
and by two vertical or oblique moving links set on a shaft passing
through the slots, such links being jointed to the horizontal fixed
links or cranks in common with the pin and hammer head. The
shaft is raised and lowered by a horizontal hand. screw motion at
the top of the plates and gearing with the shaft or its accessories.
The object of these arrangements in regard to the hammer is to
effect by artificial means the exact motion of the human arm, so as
to bring the hammer head square or in line with the chisel. In
order to increase or decrease the intensity or power of the blow of
the hammer according to the position of the file blank to be cut,
apply a spring or india-rubber cord or other elastic fabric behind and
attached to the shoulder piece, and by tightening or slackening this
spring by means of a wheel and screw the object is effected. At the
instant the blow is struck a buffer or cam motion applied to the elbow
joint by means of a back stem, disc, and india-rubber, or other equivalent
serves to catch the recoil of the hammer, and prevent any tremor
on the chisel head. In order to raise the hammer head clear of the
chisel while the machine is at rest, or whenever necessary, a crank
handle is attached to the main shaft or fulcrum of the hammer arm
on the outside plate opposite to that containing the driving pinions;
this crank traverses a quadrant bar, and is fixed thereon by means
of a spring catch or pin, so as to elevate and set the hammer as may
be desired.
I now proceed to describe the arrangements appertaining to the chisel
and chisel holder-On each side of the sliding bed plate a vertical or
oblique rocking arm is set on a pivot, and carries a horizontal bar extending
towards the front of the machine, and between these bars a transverse

page_text: bar is fixed, so that the whole oscillates to and fro as one piece (as here-
after described). On this transverse bar the arm of the chisel holder is
borne the arm consists of a strong bracket piece cut through to fit the
transverse bar, to which it is secured by a screw and nut, and a sliding or
tightening strip, which is accomplished by a hand wheel and screw set in
a bearing on the transverse bar, thus allowing it to be shifted on the bar
to any required position to suit the position of the hammer and file; the
arm terminates by a jointed face or flange from which a lever is extended
vertically, and to the top of which a screw working in a female socket
on a bracket is connected, whereby an up or back action or tilt is
given to the chisel holder by aid of a worm wheel working in outer
teeth of the socket. To this arm the holder of the ohisel is bolted or
otherwise secured, the holder consisting of a socket and flange in
which the ring containing the chisel is borne, the ring being secured
in the socket by tightening screws or pins, or both, which serve to
maintain the position or angle of the chisel corresponding to that of
the hammer. On the side of the machine opposite to that containing
the driving action the feed motion to the slide rest, hammer, and chisel
are given as well as the lifting motion for the chisel. Now the rocking
arm on this side of the machine is made of sufficient length to descend
some distance below the sliding bed, and attached to its lower extremity.
is a connecting rod actuated from an excentric which is set on a
shaft between two brackets underneath the main driving shaft, which
shaft carries a pinion working under sliding plate at the end of the open
space; this pinion gears into an under pinion on the excentric shaft,
and thus the rocking motion is given through the excentric and
connecting rod direct to the oscillating arms by which the transverse
bar carrying the chisel holder is controlled. Outside the external
bracket carrying this last arrangement the shaft is continued, and also
carries a second excentric and connecting rod extending obliquely down-
wards and towards the rear of the machine; this rod is then connected
to an ascending lever and disc, rocking on an axis in line with the ex-
centric, such axis being borne by a transverse bracketed bearing bolted
to the sliding rest or bed; the disc carries a ratched pall which gears
into the teeth of a wheel set and fixed on the axis close to the loose disc,
and a spring, catch pall is arranged on the other side of the toothed
wheel, so that at each revolution of the machine the wheel is moved
one or more teeth as required. This axis or shaft held by the external

page_text: bracket as above passes through bearings in the sliding bed, and serves
to communicate the entire feed motion to the sliding bed by means
of the pinion formerly described gearing with the fixed rack on the
anvil.
Figures 1 and 2 are slide elevations of the machine; Figure 3, a plan
view of part thereof; Figure 4, an enlarged side view of the hammer
action. Similar letters denoting corresponding parts in each Figure.
a, is the anvil set on a block of stone and containing the rack b,
Figure 3, and file with holder; c, is the travelling carrier on which all
other parts of the machine are borne; d, is the driving shaft and d'
the position of the driving pulley. The bevel wheels described
previously terminate by the arrangement shewn at e, e, whereby the
cam shaft and cam fare operated. The hammer action will be clearly
understood; g, is the shaft and g¹ the handle attached thereto capable
of adjustment on the quadrant g³; h, the turn wheel to elevate or
depress the bearings of the hammer side arms in the slot h'; i, i, the
arrangement for tightening or slackening the india-rubber hammer
springs, motion being taken for the cam shaft f, the diagonal crank
rod works the slotted bar and and rack, behind which a pair of bevels turn
the horizontal shaft and cog wheels, whereby the endless screw i
Figure 3, is made to tighten or slacken the india-rubber or other
springs as required. This motion is easily adjusted by hand at the
commencement of work. The buffer arrangement is shewn at j, j; kis
the turntable carrying the vertical plates within and outside which
the above actions are set; 1, is the transverse slide bed containing
tenoned grooves ', P, for the travel of the turntable action so as to
enable the hammer action to be set at either side of the machine, and
to be turned to the angle required; m, m, the fixed rack with cogged
wheel gearing and clutch for return motion of traveller when the length
of file has been cut, the gearing is supported in a suitable bracket bolted
beneath the traveller.
In Figure 2, n is a connecting rod set excentrically on the driving
shaft; it communicates a rocking motion to the racket motion n' suitable
palls being applied) and thence to the pinion shaft n² (Figure 3), whereby
the pinion n³ between the anvil rack n' and traveller is moved tooth by
tooth to propel the moving parts along the course of the file. Another

page_text: excentric operates the compound rod o and rocking lever o', whereby
the chisel holder o is lifted or tilted; this rod is formed with a right
and left handed screw connected by a tube with corresponding internal
screw threads, it is therefore capable of very great adjustment to suit
its required action. 02 being the chisel holder. p is the chisel secured
therein by suitable fastenings. In Figure 1 p' is a link in connection
with the holder by a block and screw nuts, the link works in a pin
joint in the curved arm på, and p³ is a screw passing through the
standard q but not turning therein. It is clear that any movement of
this screw will regulate the angle of tilt to the chisel.
In Figure 3 an endless worm wheel is shewn over the slide on
the transverse bar; this is turned by a key or handle and gears with
a hollow pinion through which the screw p³ passes in a female
thread, then the outside of the pinion is cut with a thread the reverse
way of the internal screw, so that the uppermost endless screw or
worm wheel works the pinion and thereby drives the screw p³ without
turning it round.
From the foregoing description the unison of the motion of the
machine will be comprehended. A fast and loose pulley being placed
on the main driving shaft, power is communicated by a driving strap
from an engine, the various bevels and the hammer action being so
arranged that the hammer shall descend on the chisel immediately the
lifting apparatus has been drawn out of action, so as to enable the
chisel to rest on the surface of the file blank; the cam or volute on
the driving shaft of the hammer arrangement raises and releases the
hammer at the exact moment for the blow; then the lifting, excentric,
and feed motions act, and the slide bed and all the working parts are
drawn simultaneously rearwards to the exact distance for the next tooth
to be cut, again the chisel descends, and again the hammer strikes its blow.
On starting the machine the corner of the file at its point is first cut,
and since this portion of the file is thinner, and the width of the tooth
to be cut is less than in any other part, it follows that the blow of
the hammer should be proportional to the work, therefore the india-
rubber or other springs attached to the elbow movement are slackened,
and consequently the blow of the hammer is decreased, the chisel holder
is drawn on the slide, so as to bring the centre of the chisel over the
centre of the width of the cut; this is effected by the hand wheel

page_text: and screw on the transverse bar of the chisel holder, and therefore as
the file blank is travelled over the chisel is shifted further over it, and
the hammer is made to strike harder until the chisel is fairly at work,
or the cut set in the blank, the file blank is kept firmly down on its bed
by a pressing roller set in an arm attached to a transverse shaft working
in the steps of the slide rest, a crank or lever being attached to it and
connected to a spring, a powerful leverage is given to the roller, which
travels along the file in common with all the moving parts; it can be
released directly the file is cut. The angle of the chisel can be arranged
so as to over cut and up cut by fixing the transverse bar in corres-
ponding diagonal bearings; then, as before stated, the hammer seat or
bed is to be moved across the transverse slotted rest, and turned as a
turntable so as to throw the hammer to the corresponding angle of the
chisel; but in practice where several machines would be in work it
will be found preferable that some should be set for the over cut and
others for the up cut, as required, to save the necessity of altering the
transverse bar as well as the hammer and chisel.
The details of the machine above given serve to shew the general
principles of the Invention, whereby a stationary and unyielding file
blank set immoveably on an anvil bed is made to sustain the regulated
and unvarying blows of the hammer and chisel, but it is obvious that
modifications of these actions. can be substituted without in any way
departing from their effect, for example, the arrangement of the bevels
for driving the hammer may be varied, and yet the same result may
be produced, and so also the shifting of the tool holder on the transverse
bar, and the elastic strain on the hammer may be worked in unison
by convenient gearing. So also the chisel holder arrangements may
be varied, and a turntable movement or other equivalent substituted
for the means described of changing its cutting angle. With regard
to the connections or supports between the transverse bar which
carries the chisel holder and the travelling bed, either bell-crank
lever supports may be used or simply rocking bars, the object being to
permit the to and fro reciprocating motion of the chisel holder.
prefer to bring an arm from the transverse bar, and to attach thereto
one or more india-rubber springs connected to the travelling bed,
whereby the blow of the chisel is deadened or prevented from recoil.
The tightening of the india-rubber spring attached to the elbow of
I

page_text: the hammer is rendered self-acting by the arrangement shewn at
Figure 2, where the rod extending from the cam shaft operates the
slotted rocking lever and ratchet motion and (by the intervention of the
bevel wheels) the shaft by which the pinion wheels are worked which
turn the tightening screw of the spring.
In lieu of bringing back the travelling bed by means of the feeding
rack, I apply a rack as shewn at Figure 1 to the side of the anvil,
then by the three cog wheels worked by the main shaft and secured by
the bracket the return motion is effected by merely shifting the handle
of the clutch, the traveller running back at once ready for a fresh
cutting operation, thus saving time and hand work, and avoiding the
chance of straining the feeding rack motion.
Having now described the nature of my said Invention, and the
manner in which the same is to be carried into practical effect, I would
remark that I do not restrict myself to the exact details or configuration
of parts I have expressed and shewn as many variations or modifi-
cations thereof may be devised without changing the general principles
on which the Invention is based, but what I claim and desire to be
secured to me by the herein in part recited Letters Patent are,-
Firstly. The arrangement and construction of the travelling bed or
carrier on the fixed anvil bed and file blank holder, such traveller
serving to carry all the moveable or working parts of the machine
simultaneously, and consequently with unerring uniformity,
Secondly. The transverse bed or carrier in conjunction with the
turntable arrangement of the hammer action supporting such action
in the open space cut in the carrier, whereby the entire machinery in
connection with the hammer may be shifted to either end of the bed
or carrier and turned thereon to the respective reverse angles requisite
for the blow to be struck on the chisel.
Thirdly. The general construction of the hammer whereby its
operation is caused to imitate the actual motion of the human arm,
and thus to strike the necessary description of blow to form the tooth of
the file.
'
In conjunction with this action I also claim the arrangement for
tightening the spring in connection with the elbow of the hammer to
regulate the power of its descent.

page_text: Fourthly. The arrangement of the feeding rack motion operated as
described, and also the arrangement of the separate rack, cog wheels, and
clutch to effect the return motion of the travelling bed.
Fifthly. The arrangement of the chisel, chisel holder, and transverse
bar, and the means of lifting or tilting the same by the self-acting
motion described, all substantially in the manner and for the purposes
as are herein specified.
In witness whereof, I, the said William Furness, have hereunto
set my hand and seal, this Nineteenth day of January, in the year
of our Lord One thousand eight hundred and seventy.