CERTAIN IMPROVEMENTS IN MACHINERY FOR MAKING SCREWS
Year: 1828

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, LEMUEL
WELLMAN WRIGHT, of Mansfield Street, Borough Road, in the County of,
Surrey, Engineer, send greeting.
WHEREAS His present Majesty King George the Fourth, in and by
His Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Eighteenth day of September, One thousand eight hundred
and twenty-eight, for Himself, His heirs and successors, did give and grant
unto me, the said Lemuel Wellman Wright, His especial licence, full power,
solo privilege and authority, that I, the said Lemuel Wellman Wright, my
executors, administrators, and assigns, and every of them, by myself and them-
selves, or by my and their deputy or deputies, servants or agents, or such'others
as I, the said Lemuel Wellman. Wright, my executors, administrators, or.
assigns, should at any time agree with, and no others, from time to time. and
at all times thereafter during the term of years therein unexpired, should and
lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "CERTAIN IMPROVEMENTS
IN MACHINERY FOR MAKING SCREWS;" in which said Letters Patent there is.
contained a proviso, obliging me, the said Lemuel Wellman Wright, by an
instrument in writing under my hand and seal, particularly to describe and
ascertain the nature of my said Invention, and in what manner the same is
to be performed, and to cause the same to be inrolled in His Majesty's
High Court of Chancery within six calendar months next immediately after

page_text: the date of the said recited Letters Patent, as in and by the same, reference
being thereto had, will moro fully appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Lemuel Wellman Wright, do hereby describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, by the
Plan or Drawing hereto annexed, and the following description thereof (that
is to say):-
"
My Invention of "Certain Improvements in Machinery for Making
Screws consists of distinct machines to be employed in the operations of
cutting off the required lengths of material and forming the heads, and for
slitting the heads and cutting the threads or worming upon the shafts of the
screws, which are to be made of iron, copper, or brass wire, as required.
The machine for cutting off the lengths of wire and heading the screw shafts
is shewn in Sheets 1 and 2, in which Fig. 1 is a side view of the machine;
Fig. 2 is a top view; Fig. 3 is a section taken horizontally through the
machine; Fig. 4 is a view of the reverse side of the machino to Fig. 1.
a, a, a, a, is the frame on which the working parts are mounted; b, b, the
main shaft; c, c, the auxiliary shaft, with the pinion d gearing into the spur
wheel c on the main shaft. As the main cam revolves the eccentric cam f, f,
acting on the friction roller 9 attached to the fringe joints of the toggle
pieces h, h, depresses them so as to bring them nearly horizontal, forcing the
sliding bar i towards and the punch j into the cup of the dies k, and, com-
pressing the end of the wire in them, performs the first operation in heading
the shaft of the intended screw. The continued rotation of the main shaft
brings the smaller radius of the eccentric cam f.f, opposite the friction roller g,
when the cam l on the shaft m, also acting on the friction roller g, raises the
toggle joints and withdraws the sliding bar and punch, the shaft m and cam
being put in motion by the tooth wheel n on the shaft 6 taking into the
toothed wheel o upon the shaft m, see Fig. 4. A pair of connecting bars p, p,
secured at one end to the sliding bar i, are connected at their opposite ends to
the cross piece 9, which is again connected to the toggle pieces r, r, of the
feeding pincers s, s, which are mounted on a sliding plate t. As the sliding
bar i advances towards the dies, the connecting bars p, p, carry back the cross
piece and toggle joints r, r, and the pincers s, s, open; the return of the sliding
bar expanding the toggle pieces closes the pincers 8, s, and causes them to
take fast hold of a piece of wire previously entered within then, as at u, u,
and bring it through the aperture in the frame and steel cutter v into the
dies; the upper half of the dies is mounted in the vertical sliding piece w,
which, as soon as the proper length of wire is brought into the dies, is de-

page_text: pressed by a projecting piece on the under side of the fulcrum end of the
lever a, the other end of this lever being raised by the cam upon the shaft b,
acting upon the friction rollery. On the shaft m is the double or grooved
cam 1, 1, with the friction roller 2 on the longer end of the lever 3 working in
it; the shorter end of this lover works in a slot in the lower end of the
vertical cutter (as shewn by dots in Fig. 1), and depressing it cuts off the
length of wire required to form a screw shaft; the motion of the machine
proceeding as at first described, the wire is compressed into the cup of the
dies k by the punch j, and the head of the intended screw is partly formed.
At this time the cam 1 depressing the longer end of the lever 3 raises the
shorter, and with it the vertical cutter v, at the same time the retreat of the
bar i, connecting bars p, p, and cross piece q, has expanded the toggle
pieces r, r, and closed the pincers s, s, upon another length of wire, which,
with the pincers 8, s, and plate t, is carried towards the dies in the manner
before described; the cam ceasing to act on the end of the lever a, it is
allowed to descend, when a short arm 4 on the fulcrum end of the lever a, see
Fig. 2, raises the piece w to which it is connected by the bridle piece 5, and
this opens the dies. The advance of the wire u, u, in the manner before
described pushes out the partly headed shaft, when it is taken hold of by a pair
of spring clips or fingers 6, and carried away towards a second pair of heading
dies'; these fingers or spring clips are fixed to the horizontal sliding bar 7.
The friction roller on the end of the lever 9, 9, works in the groove of the
double cam 8, 8, fixed on the end of the shaft b, and as the cam 8, 8, revolves
the other end of the lever 9, 9, áttached to the sliding bar 7, 7, is moved towards
and from the machine, moving the bar and fingers with it; the fingers 6
having hold of the screw shaft carry it as described to' the middle station 10,
where it is held by one end of the lever 11, the other end being raised by a
cám 12 on the shaft m (see Fig. 8); another movement of the fingers 6
towards the dies k for another shaft causes the fingers 13 to take hold of the
screw shaft at the station 10, when, the cam 12 ceasing to act on the end of
the lever 11, the fingers 18 by the further movement of the bar 7 carry the
shaft to opposite the second heading dies 14, where the punch 15, see Fig. 3,
forces it into the die and completes the head; this punch 15 is attached to a
sliding bar 16 acted on by the cams 17 and 18, through the friction roller 19
and toggle pieces 20, 20, in the manner before described. On the retreat of
the sliding bar: 16, the connecting rods 21, 21, by the cross piece 22 and
punch 23, force the now headed shaft out of the dies 14, when it is taken hold
of by a third pair of fingers 24 and carried by the movement of the bar 7 to
the station 25, where it is held while any burr or roughness on the edge of tho

page_text: head is turned off, the screw shaft being held by depressing one end of the
bent lever 26, the other end being raised by the cam 27 on the axle m. On
this axle is another cam 28, which, as it revolves, pushes forward the bent
sliding bar 29, and with it the cutter 30 (see Figs. 3 and 4), towards the
head of the screw shaft; rotatory motion is communicated to this cutter from
the pulley 31 on the axle c by the cut band 32 to the .rigger 33 on the end of
the hollow shaft 34, which is connected by a key and slot to the cutter spindle
35, and carries the spindle and cutter round with it. The cam 28 ceasing to
act on the end of the sliding bar 29, the helical spring 36 forces back the
sliding bar 29, spindle 35, and cutter 30 to make way for the next screw
shaft brought by the fingers 24 to the station 25; the cam 27 ceasing to act
on the lever 26, allows the next.shaft to displace the now finished shaft which
falls away below.
L
The machine by which the head of the screw is to be slit, and the worm
cut upon the shaft, is shewn in the Drawings, Sheets: 3 and 4, where Fig. 5
is a plan or horizontal view of the machine; Fig. 6 is a longitudinal.section
taken through the machine; Fig. 7 is a cross section taken through the
machine at the part shewn by the red lino A, B; Fig. 8 is a cross section
taken in the direction of the red line C, D, (see Fig. 5). The several letters
refer to the same parts in all theso four Figures. A, A, are the frame standards
and cross bearers on which the working parts of the machine are mounted;
B is the auxiliary axle, turned by winch handles or by any other means;
on one end of this axle is a pinion C, taking into a toothed wheel D fixed
upon the end of the main axle. E, upon which the eccentric cams are fixed
that work the several moving parts of the machine. The shafts of the
intended screws, described as having been headed in the former machine, aro
now brought to this machine, and by the person attending it are singly placed
on to the periphery of the feeding wheel F, as at a, a, a, a, where they are held
by the springs b, b, b, b, (see Figs. 5 and 7); this feeding wheel F is fixed upon
a lateral axle G, which has also a ratchet toothed wheel II upon it, having
twice as many teeth as there are notches in the feeding wheel, and the rotation
of this wheel II causes the feeding wheel F, carrying the shafts of the intended
screws, to turn at intervals, so as to bring the individual shafts in succession
into the mouth of the chaps I as at c, where they are held while the heads are
slit. The rotation of the ratchet wheel II is caused by the movement of the
lever J, having it sfulcrum in the ears of the cross bearer, as shewn in the
Drawings. At one end of this lever is a spring tooth d taking into the teeth of
the ratchet wheel; at the opposite end of this lever is a friction roller working
on the cam K, which cam, as the main shaft revolves, raising the longer,

page_text: h
depresses the shorter arm and spring tooth, and with it one tooth of the ratchet
wheel; the continued rotation of the main axle E allows the longer end of the
lever to fall on the smaller diameter of the cam, consequently raising the
shorter arm, and the spring allows the tooth d to give way to the next tooth of
the ratchet wheel until it has passed, when it forces the spring tooth into the
next ratchet tooth, which is depressed in like manner by the continued rotation
of the cam K; and this produces an interrupted rotatory motion, by which the
scrow shafts are successively brought into the mouth of the chaps I, with their
levers working on a centre pin on a vertical plate (see Fig. 7); the chaps are
made to close and take fast hold of the screw shaft by the cam L depressing
the longer arm of the lever M (see Fig. 6), the shorter arm of which works in
a mortice hole in the sliding piece e, kept in its position against the plate by
guide pieces f, and its lower end jointed to the toggle pieces g, g, connected to
the lower ends of the legs of the chaps I. The toggle pieces being thus brought
towards the horizontal position, expand the legs of the chaps and cause the
mouth to close, and firmly hold the screw while the head is slit. The con-
tinued rotation of the main shaft brings the cam N into operation on the
friction roller at the longer end of the lever O, and raises the shorter end,
which is formed with two arms, to carry the small spindle turning on screw
centres; upon this spindle h, is the rotatory cutter i and small pulley j, which
receives motion by a band k from the large rigger on the auxiliary axle B.
As the longer end of the lever O is depressed, the shorter end rising with the
cutter, carries it through the centre of the shaft head, the rotatory cutter
forming the slit in the head as it rises; this being done, the cam N receding
from the longer end of the lever O, the cutter is allowed to descend. During
this operation the feeding wheel is moved on by the ratchet wheel being
depressed one tooth, leaving the screw shaft in the chops opposite the centres
between the notches in the feeding wheel, and at this time the bent holder mis
allowed to rise and support the screw shaft, by the movement of the bar 20,
hereafter described, carry away an inclined plane from under the end of the
pin n attached to the lever o, the other side of the lever carrying the holder m;
the cam L receding from the end of the lever M allows the shorter end to
descend, carrying the toggle pieces with it, and opening the chaps to allow
of the screw shaft being pushed through the chaps into the mouth of the
stationary tube P by the punch p; the reverse movement of the bar 20
bringing the inclined plane under the end of the pin n, causes the bent holder
m to descend out of the way of the punch p as it advances after the screw
shaft has partly entered the tube P, where it is held by a pair of small springs
which clasp the shaft; the punch p is made to advance by the cam Q acting

page_text: against the friction roller at the end of the sliding bar R; and when the cam
Qreceiles from the end of the bar R, the bar and punch p are drawn back
by a helical spring 2 on its upper side, attached at one end by a pin to the
bar, and at the other end to any fixed part of the frame. The screw shafts
being thus successively forced into the tube D after being slit, are projected
forward to the opposite end of the tube and into the chaps r, r, where they
are held and turned while the screw thread is being cut on them. These
chaps are mounted on the end of the tubes s, 3, surrounding the stationary
tube P. The scrow shafts having been projected forward, the chaps are then
closed by the cam t operating on the friction roller v on the sliding bar u; at
the end of this sliding bar is a pin working in a slot in the cross lever w; this
lever works on a pin as its fulcrum at one end; the other end is formed into
two bent arms, cach having a friction roller on its end working in the clutch
box ; this clutch box a is connected by joints to the toggle pieces y, y, which
are again connected to the longer arms of the levers,, working on pins 1, 1,
as their fulcrums; the shorter arms of these levers work in mortice holes in
the sliding pieces of the chaps r, r, and which are kept in their places by the
covers 2, 2. It will thus be seen that as the cam t, the sliding bar u, and
lever w slide the clutch q box a along the tube a, the toggle pieces y, y, will
come into the vertical position, expanding the longer arms of the levers =, <;
the shorter arms depressing the sliding picces cause the chaps 1, 1, to take fast
hold of the screw shaft, which will revolve with them and the tube s in the
alternating rotatory motion communicated to the tube through the pinion S,
which is acted on by the rack T working in guide pieces. The lower end
of this rack is connected by a joint to the longer arm of the lever U, having
its fulcrum in the top of the rocking crutch V, and its shorter end connected
by the rod W to the crank X, which is on the auxiliary axle B. Thus, as the
crank X revolves, it alternately raises and lowers the rack T, which is kept in
a vertical position by the guide rollers Y, Y, working between the parellel
pieces Z, Z, on each side of the rack, the racking crutch V working with the
lever according to the position it assumes. Rotation being thus commenced
to the tubes, it is made to advance and recede by the leading screw on its end
working the stationary dies, and which leading screw must be of the same
rake or thread as that intended to be cut on the screw shaft; the keys 4, 4,
of the pinion S work in a slot in the tube s, so as to allow of the pinion being
kept in gear with the rack T without reciprocating with the tube, by the
clutch picce 5 working in a groove at the end of a pinion. The screwing dies
6, 6, are fixed in the levers 7, 7, which are mounted on pins 8, 8, on an
upright plate 9 fixed on the frame, see Fig. 8, and are brought together

page_text: closing upon the screw shaft by the action of the spring 10, and the alternating
rotatory and reciprocating motion being communicated, as described, to the
screw shaft, the worm or thread is cut upon it by the dies, which operation
being compleated, the screwing dies are made to open by the cam 11 depressing
the longer arm of the lever 12'and raising the shorter arm, which works in a
mortice in the sliding piece 13, the lower end of which is formed into cross
arms connected by the pieces 14, 14, to the lower end of the levers 7, 7, and
which, as it is raised by the lever 12, bringing the connecting pieces nearly
horizontal, expands the levers 7, 7, and opens the dies 6, 6. The screws thus
released from the dies, the chaps r, r, are made to open by the cam 15 on the
main axle acting against a friction roller 16 on the bar u, and sliding it the
reverse way to that before described where the lever moving back the clutch box
a, the toggle pieces y, y, raise the shorter arms of the levers, 2, and with
them the sliding pieces of the chaps r, r; the next movement of the punch p
projecting a shaft into the tube P and another into tho chaps to be screwed.
The finished screw is taken hold of and carried away by a pair of small spring
fingers or clips on the end of the sliding bar 18; this bar is connected by an
arm 19 to the sliding bar 20, which is acted on by the cam 21 on the end of
the main axle E; this cam, as it revolves, keeps the finger clips 18 from
entering the screwing dies until the screw is finished, when, on the dies opening,
the sliding clip is drawn by a helical spring 22 on the bar 20 into the dies, and
takes hold of the screw. Previous to the chaps r, r, opening on this, the cam
21 pushes the bar 20 into its former position, and the clips and bar 18, with
the screw, are drawn away from the dies, and the end of the screw
striking against a stationary piece 23, it is pushed out of the clips and falls
away below; this motion of the bar 20 causes the inclined plane to act under
the pin n before mentioned. On the next screw shaft in the chaps r, r, being
held ready to be screwed, the cam 11 ceasing to act on the longer end of the
lever 12, the shorter end is allowed to descend, carrying with it the piece 13,
and the connecting pieces 14, 14, when the spring 10 closes the dies upon the
screw shaft.
Another mode of mounting the screwing dies is shewn in Sheets 5 and 6,
Figs. 9, 11, and 12, where a, a, is a vertical plate fixed to the frame, and b, b,
the levers of the screwing dies, having their joints at c, c, and connected
by two pins or studs d, d, to the sliding pieces c, e, carrying the screwing
dies f, f; the closing of the dies and their pressure on the screw shaft being
effected by the springs 9, g, the pressure being regulated by the adjusting
screws h, h, in the manner shewn in the Drawing. The opening to release
the screw is effected by a wedge-shaped piece i in the end of the lever 12,

page_text: entering as it rises between the end of the arms j, j, on the levers b, b, and
thus separating them and the dies. On the descent of the shorter arm of the
lever 12, and the wedge piece i, the springs 9, g, close the dies upon the shaft
of the screw.
When it is desirable to separate the two operations of slitting the head and
cutting the thread or worm of the shaft, all the parts relative to the former are
to be removed from the machine, and the slitting be performed by a separate
machine or by hand. As there are so many different ways of performing this
operation, it is unnecessary to describe any particular mode by which it may
be done; the operation of cutting the thread or worm on the shaft will then bo
performed in the following manner, reference being had to Figs. 9, 10, 11, and
12; Sheets 5 and 6. The screw shafts being placed in the feeding wheel
and brought opposite to the end of the tube P, in, the manner before described,
the punch pushes the screw shaft into the mouth of the chaps 9, 9, on the legs
or levers r,, which are brought together and closed on the screw shaft by the
springs, and hold it, while the movement of the ratchet wheel I removes
the spring of the feeding wheel F, previously holding it away from it, when the
cam Q forcing the bar R forward, the punch p pushes the screw shaft into
the tube P; the wedge pieco t on the end of the bar R entering between the
friction roller u, u, on the legs r, r, of the chaps, opens them and allows the
screw shaft and punch p to pass through them; this movement forcing another
p'to
shaft into the chaps r, r, the operation of cutting the worm and finishing the
screw proceeds as before described.
Having thus described both generally and particularly the construction and
operation of my improved machinery for making screws, I hereby declare that
I do not mean or intend to claim separately as my Invention any of the different
parts of which these machines are composed, but I do hereby claim the com-
bination, arrangement, and application of them for the said purpose of making
screws in the manner herein described, and particularly-
In the mode of opening and closing the tongs or pincers which supply the
heading machine with wire.
In the mode of fitting up the parts of the first heading dies, and of holding
the wire while it is being headed.
In the mode of moving the cutter which cuts off the required: length of
wire.
In the manner of giving motion to the punches for heading the screw shaft
through the toggle joints and cams, as described.
In the manner of giving motion to the tool or cutter for turning or finishing
the head.

page_text: In the arrangement and construction of the feeding wheel of the notching
and screwing machines.
In the manner of notching or slitting the screw heads, as described.
In the arrangement and construction of the revolving holding chops.
In the method of feeding the same through the tube, as described.
In the mode of giving alternating rotatory and reciprocating motion to the
same, as described.
In the mode of constructing and mounting the dies, by which the thread or
worm is cut on the screw shaft; and in the manner of disengaging the screw
and carrying it away to make for the next shaft.
In witness whereof, I have hereunto set my hand and seal, the
Eighteenth day of March, in the year of our Lord One thousand
eight hundred and twenty-nine.