AN IMPROVED MODE OF AND APPARATUS FOR MANUFACTURING FILES
Year: 1860

page_text: LETTERS PATENT to Thomas Greenwood, of Leeds, in the County of
York, Machine Maker, for the Invention of "AN IMPROVED MODE OF AND
APPARATUS FOR MANUFACTURING FILES,"
Sealed the 4th December 1860, and dated the 19th September 1860.
PROVISIONAL SPECIFICATION left by the said Thomas Greenwood at
the Office of the Commissioners of Patents, with his Petition, on the
9th September 1860.
I THOMAS GREENWOOD, of Leeds, in the County of York, Machine Maker,
do hereby declare the nature of the said Invention for "AN IMPROVED MODE
OP AND APPARATUS FOR MANUFACTURING FILES," to be as follows:-
The ordinary mode now in use for forming file blanks is by forging. I now
propose to accomplish this by means of a rolling machine, the grooves in the
rollers which are so formed that part of the surface of each roller represents
a side of the file to be produced. The shaping of the rollers is effected by
causing a proper template to be pressed against the roller, and opposite to the
template a proper cutting or grinding apparatus; the template receives at the
same time a traversing reciprocating motion extending to its full length, and
the rolier also receives a rotatory reciprocating motion to the same extent, the
surface speeds of the template and roller being of course the same. By this
means thecutter is made to produce a copy of the template on a portion of the
periphery of the roller. The requisite number of steps or graduated surfaces
are thus produced upon each set of rollers, so as to admit of passing the blank
[Price 8d1

page_text: several times between the rollers so as to secure perfect accuracy of form.
By this process we produce rollers of the required pattern or form for rolling
most descriptions of files.
In the rolling machine pairs of these rollers are geared together in the
usual manner, and a piece of steel of the proper weight and length to form
the blank,after being heated sufficiently, is presented to the bite of the rollers,
and enters between them at the recessed part. This operation is repeated
upon each graduation of the rollers.
The next operation in the process of manufacturing files is to cut the tang.
This I propose to perform upon a trimming machine, in which a slide carrying
suitable cutting tools is made to work on an inclined bed, and a suitable
resting place or holder is provided for the blank. The slide is made to descend,
and one of the cutting tools cuts off such parts of the blank as is necessary to
be done to form the tang. The resting place or holder is made of such a form
as to allow these parts when cut off to fall away into suitable receptacles. The
blank is then turned round by the operator and the tang placed in a suitable
recess formed in the resting place or holder, which acts also as a gauge for the
length of the blank, and as the slide descends another suitable cutting tool
shears off the end or point of the blank, thus reducing the blank to the proper
length.
The next operation is to anneal the blanks, which I prefer to do in cast iron
boxes containing from one hundred to two hundred blanks each. The blanks
are placed upon their edges and so as not to touch each other, and the inter-
stices are filled up with sand and sawdust in about equal quantities. The
boxes are placed in a reverberatory furnace, where they are slowly heated to a
proper degree, and afterwards allowed gradually to cool.
The next operation is to pickle the blanks for the purpose of removing the
scale. This I effect by immersing them in dilute sulphuric acid; I then
remove them from the solution and wash offany acid that may adhere to their
surfaces. This operation reduces very much the difficulty and cost of grinding,
which is the next operation, and for which purpose I employ by preference a
grindstone of a peculiar construction.
A strong cast iron disc or wheel is mounted upon a strong shaft and suitable
journals. On each side of this disc or wheel are mounted segments of stone;
these stones are dovetailed on the side which comes against the flat side of the
discor wheel, and are held in their places by bevilled flanges and plates firmly
bolted against the wheel or disc. These stones which are fitted round each
side of the disc form two flanges, and are dressed up to a true surface in the
usual manner. Four compound slides are provided, two on each side of the

page_text: disc, to receive a blank each. These slides are actuated by a lever for the
purpose of pressing the blanks against the stone. The transverse slide is
actuated by a vertical lever, and a rocking motion is imparted to the saddle or
file holder, so as to present the surface of the blank properly to the stone.
By the use of this combination face grinding it will be understood is sub-
stituted for grinding from the periphery. The slides and holders above
mentioned may also be applied to grindstones of the ordinary construction.
The next operation is what is technically called "stripping," to perform
which I construct a machine containing two or more reciprocating arms (by
preference four are used). In each of these reciprocating arms is mounted a
weighted lever carrying a file. The blank to be operated upon is placed in
bearings upon a table which has a slow reciprocating motion in a transverse
direction to the motion of the arms. The weighted lever carrying the file is
then brought down upon the blank, and by its reciprocating motion the
surface of the blank is stripped or drawfiled by means of the file it carries for
that purpose.
The next operation is to cut the blank, which I prefer to do in what is
known as Bernot's Patent File-cutting Machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Greenwood in the Great Seal Patent Office on the
19th March 1861.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, 'THOMAS
GREENWOOD, of Leeds, in the County of York, Machine Maker, send
greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Nineteenth day of September, in the year of our
Lord One thousand eight hundred and sixty, in the twenty-fourth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas Greenwood, Her special license that I, the said Thomas Green-
wood, my executors, administrators, and assigns, or such others as I, the
said Thomas Greenwood, 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 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 "AN IM.
PROVED MODE OF AND APPARATUS FOR MANUFACTURING FILES," upon the condition

page_text: (amongst others) that I, the said Thomas Greenwood, by an instrument in
writing under my hand and seal, 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 Thomas Greenwood, do hereby declare
the nature of my 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 Drawings hereunto annexed, and to the
letters and figures marked thereon (that is to say):-
This Invention relates to certain improvements in the process of manu-
facturing files, the object being to effect an economy in their manufacture. In
carrying out the manufacture I propose to use in combination certain opera-
tions which are well known to some branches of the hardware manufacturers,
but which have never been applied to the manufacture of files, and with
respect to those operations which are commonly used in the preparation of file
blanks I propose to introduce modifications in the machinery by which such
operations will be materially improved; thus by the combined use of these
several means I am enabled to introduce to the trade a new mode of manu-
facturing files.
The plan hitherto adopted for forming file blanks is to forge them by hand
to the required shape. Instead of this laborious and expensive operation I
propose to attain the same end, first, by means of grooved rollers,in which the
grooves are cut out or formed by means of a cutting tool, which is guided by a
profile or blank of the desired form. These grooved rollers are mounted and
driven in the ordinary manner adopted in rolling mills, and a piece of steel to
form the blauk (cut to the proper length, and being of suitable weight) is
passed while in a heated state under or between the bite of these rollers, and
is thereby reduced to the embryo shape of the blank by pressure. The blank
is then transferred to a trimming machine, in which the tang is cut and the
blank is reduced to its proper dimensions.
The next operation is to anneal the blanks, and this is done by packing
them in cast-iron boxes, which are then subjected to the heat of a rever-
beratory furnace, and afterwards allowed to cool gradually. During the
annealing operation scale will be formed upon the blanks, and in order to
remove this I resort to what is known in the wire-drawing and some other
trades as the "pickling" operation, which will greatly facilitate the removal of
the scale. The acid used in this operation having been removed from the

page_text: blank by washing, I submit the blanks to the action of a novel construction of
grindstone, presenting them to the sides instead of to the periphery of the
grindstone, which arrangement permits of the operation being effected in a
better and more economical manner than heretofore. When ground the blanks
are ready to undergo the operation of "stripping," the object of which is to
remove the cross grain produced by the grinding surfaces. This operation I
effect by a novel arrangement of machinery, which serves to give a slow lateral
motion to the file blanks and a reciprocating motion at right angles thereto to
a file surface, which is brought down to act upon the blanks and strip or
"drawfile" them. The file blanks having been thus treated are ready to
undergo the operation known as file-cutting. This operation may be effected
by hand, as heretofore, but I propose to employ what is known as Bernot's
Patent File-cutting Machine.
I will now proceed to describe more in detail the nature of my improved
mode of manufacturing files, and also the construction of the machinery which
I employ in preparing files for the finishing or file-cutting operation.
In Sheet I. of the accompanying Drawings I have shewn the machine,
whereby the grooves are cut in rollers of the rolling machine, which I propose
to employ in lieu of the forging process for commencing the shaping up of the
file blank.
Fig. 1 is an end elevation; and Fig. 2 is a front elevation of the machine.
A is the framework and bed of the machine; B is a shaft, upon which are
mounted the driving pulleys C, C; on one end of this shaft is the spur pinion a
taking into the spur wheel b; into a slot in this wheel is fixed a crank pin c
attached to the connecting rod d. This rod is jointed to the vertical slide D,
which works in suitable guides in the framework A, and also against the fric-
tion bowles e; f* is a template, or copy of one side of a file blank, and is fixed
in the slide D; H is a moveable plummer block, in which the roller L to be
operated upon rotates, and is securely held in any convenient manner; is a
friction bowle, mounted in a projection of the moveable plummer block H;
this plummer block is pressed against the template or copy f* by means ofthe
spring g; h is a spur wheel, keyed on the end of the roller L, the pitch line of
which wheel is of the same diameter as that of the roller L; i is a toothed rack,
mounted on or attached to the slide D, and when this slide is actuated by the
crank wheel 6 it will give the same surface speed to the roller Las is imparted
to the template or copy f* of the file blank; K is a small headstock, carrying
a spindle and cutter or grinding apparatus, which is set up by the screw and
handlej, and as the roller Ladvances towards and recedes from the cutter the
latter produces or forms a recess in the roller L corresponding with the form

page_text: of the template or copy f* placed in the slide D. The rollers thus made with
grooves, corresponding to the intended shape of the blanks, are then mounted
and worked, as before mentioned, in the ordinary manner, and pieces of steel,
of which the files are to be made, are first heated and then passed while in a
heated state between the grooved rollers, and are formed by pressure into the
required shape.
The next operation is to cut the tangs and to reduce the blank to the proper
dimensions.
Fig. 3 is a side elevation; and Fig. 4, a front elevation of the machine for
cutting or forming the tangs of the file blanks; Fig. 5 is a plan view shewing
the apparatus for holding the blank while under operation.
A is the main framing of the machine; B, B, the fast and loose pulleys for
driving the main shaft; C is a pinion upon the main shaft and gears into and
drives the spur wheel D upon the excentric shaft E, whereby motion is given
to the vertical slide F.
The cutters are shewn at a and b; the bottom one a of which is made to
correspond with the shape of the tang. The upper cutter 6 is fixed in the
slide F, and is grooved out to fit upon the bottom cutter a, so that when the
end of the blank is laid properly upon the bottom cutter a, the upper cutter 6
comes down and cuts off the two sides from the blank. The pieces thus cut
off fall away and leave the tang perfect. The blank is then turned round, and
the end of the tang being placed against the stop c (Fig. 5), the cutters d and e
shear off the opposite end to the desired length. The file blank after being
annealed and pickled as above mentioned to remove the scale therefrom will be
ready to be ground.
Fig. 6 is a plan; Fig. 7, a side elevation; and Fig. 8 is the back elevation
of a machine for grinding file blanks; Fig. 9 is a plan view; Fig. 10, a side
elevation; and Fig. 11, a back elevation of the principal parts for holding flat
files, shewn detached, and drawn upon an enlarged scale.
a, a, is the grindstone; b, b, is the bed plate, which carries the slides;
c, c, is the upper slide, which moves to and from the stone by means of the
lever d. A transverse slide e is actuated by the vertical lever g, g, by which
the file can be moved to and fro against the surface of the stone. The file
holder h is made to swivel upon the axis i by means of the lever 1, 1, and thus
presents all the parts of the curved surface of the file to the stone. The
apparatus shewn in Figures 9, 10, and 11 is for grinding the flat sides of hand
or taper files, and it is only the top part or file holder which is varied for the
three other apparatus so as to be enabled to grind round, half-round, and
the edges of flat and hand files.

page_text: Fig. 12 is a plan ; and Fig. 13, a side elevation of the file holder for round
files. In this case the file is held up by the levers and swivelling holder, as
before, and the file is turned round on its axis by a handle j.
Fig. 14 and Fig. 15 are plan and side elevations of the contrivance for
holding half-round files while grinding the curved side; k, k, is a file holder
mounted upon two journals and made to turn partially round by means
of the lever m, m. The file is fixed to one side of this turning holder at
such a distance from its axis as to produce the required curve when ground
properly.
Figures 16 and 17 are similar to Figures 9, 10, and 11, with the addition
of clamps to hold the file firmly to the bed while grinding, as the stone in this
apparatus is made to turn in the opposite direction. It will be seen that
in my improved grinding apparatus the blanks are brought against the
sides of the stone or grinding surface, and not against the periphery, as is
usually the case.
The next operation to which the blanks are submitted is the "stripping" or
drawfiling operation for the purpose of taking off the grain; Fig. 18 is a plan
view; Fig. 19, an end elevation, and Fig. 20, a front elevation of my improved
machine for stripping files or taking off from the blanks the grain that has
been given to them by the grinding operation. The file blanks a, a, are
secured flat on a table 6 by means of adjustable screw clamps c, c, which hold
them securely against block pieces fixed on the table b, which is mounted on
V-guides b', Fig. 19, and a slow reciprocating horizontal motion is given to the
table by means of a worm d on the shaft e. This worm gears into and drives
a worm wheel f, and the motion of this wheel is by means of the connecting
rod g transferred to the table b, as will be clearly understood by referring to
Fig. 20.
A hammer head h at one end of a lever i is provided on its face
with a steel scraping toolj, with a file surface, which rests on the face of the
file blank. The lever i is jointed to a sliding block k, which is moved to and
fro on guides 1, 1, by means of the slotted wheel m, to which the block / is
connected by the link n. The attachment of the link to the wheel m may be
made at any distance along the slot from the axis of the wheel m, according
to the desired length of stroke. The operation of the machine is as follows:-
A file blank having been secured on the table of the machine, and the scraper
of the hammer head having been brought down on to the face of the blank,
the wheel m is set in motion and the scraper is thereby drawn to and fro
along the face of the blank; at the same time an endway motion is given to
the table b, so that as the scraper moves to and fro its teeth may never act
against the same part of the surface of the blank, and consequently there

page_text: will be no danger of cutting lines in the blank. When it is desired to remove
the scraped blanks, the hammer head h is lifted up by means of the handle o,
and is held up by causing the handle to be retained by a spring catch p. It
will be seen in the Drawing that several blanks may be operated upon simul-
taneously by multiplying the parts, and that provision is made for stopping one
of the scrapers or other parts of the machine, by throwing the same out of
gear without interfering with the other parts. The blanks having been
stripped or drawfiled on both sides will then be ready for cutting, which
may be performed by any suitable machinery, but I prefer to use for that
purpose the machine known as Bernot's machine.
Having now set forth the nature of my Invention of "An Improved
Mode of and Apparatus for Manufacturing Files," and explained the manner
of carrying the same into effect, I wish it to be understood that I lay
no claim to any of the consecutive operations above detailed when used
irrespective of the preceding or following operations, but what I claim is
the combination of operations above described for the purpose of facilitating
the manufacture of files and the machinery or apparatus above described
with reference to the Drawings for aiding in obtaining that result.
In witness whereof, I, the said Thomas Greenwood, have hereunto set my
hand and seal, the Eighteenth day of March, in the year of our Lord
One thousand eight hundred and sixty-one.
THOMAS GREENWOOD. (L.S.)