IMPROVEMENTS IN MACHINERY FOR MANUFACTURING SCREWS
Year: 1870

page_text: LETTERS PATENT to Alfred Vincent Newton, of the Office for Patents,.
66, Chancery Lane, in the County of Middlesex, Mechanical
Draughtsman, for the Invention of "IMPROVEMENTS IN MACHINERY
FOR MANUFACTURING SCREWS." - A communication from abroad by
-
Jared Augustus Ayres, of Hartford, in the State of Connecticut,
United States of America.
caled the 28th June 1870, and dated the 25th February 1870.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on
the 25th February 1870.
I, ALFRED VINCENT NEWTON, of the Office for Patents, 66, Chancery
Lane, in the County of Middlesex, Mechanical Draughtsman, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN MACHINERY
FOR MANUFACTURING SCREWS," to be as follows:-
―
These improvements relate to the cutting of the thread upon headed
screw blanks, and have for their object mainly to render the machine
used for this purpose automatic in its action, and to give greater

page_text: each other so as to leave a vertical space between them sufficient to
receive the shanks of the blanks fed thereto as the hopper is rotated.
The hopper is mounted on a horizontal stud axle carried by a bracket
from the end of the machine. The inner side of the hopper has a large
circular opening through which the headed blanks are thrown pro-
miscuously into the hopper. The hopper is rotated by a ratchet operated
by a tappet cam. Around the interior edges of the space between
the bases of the cones are several sets of curved races projecting
towards the centre of the hopper. By the rotation of the hopper those
blanks which have arranged themselves shank downwards in the space
between the cones will be lifted up and discharged into a curved fixed
guide which leads down through the central opening towards the grippers
for receiving the blanks. The blanks in passing down this fixed guide
will move from a vertical to a horizontal position, and will severally fall
on to the upper surface of a horizontal cylinder (formed on the top of a
standard). Fitted to this cylinder is a segment cap forming part of a
rocking sleeve shaft, and fitted to the sleeve shaft is an elastic finger
between which and the edge of the segment cap the blanks are severally
received. By the rocking axial motion of the cap around the cylinder
the blank held between the cap and the finger will be carried down to
the axial line of the hollow mandril and deposited in a semicircular
groove cut in the face of the cylinder. The head of a sliding rod
mounted upon the boss of the cap is by this axial motion brought
between the prongs of a rocking lever, which being operated by
a cam will traverse forward the blank and thrust the head into the
opened jaws of the mandril. The mandril is mounted in bearings

page_text: in standards and provided with fast and loose driving pulleys for
communicating motive power to the machine. One end of the mandril
is made hollow to receive a pair of gripping jaws which are pivotted
near their outer end, the other extending inwards and terminating in
a spring. Between the spring ends of these gripping jaws a wedge
is thrust or withdrawn to cause them to grip the head of the blank
or disengage the finished screw. This wedge is carried by a sleeve (upon
the mandril) provided with a rib fitted into a groove in a ring mounted
in journals at the end of a rock lever. The opposite end of this lever
is operated by tappets attached to the back of a spur wheel on the end
of the main cam shaft of the machine. This wheel is driven by a
train of spur gear from the mandril. The chasing tool holder is carried
on a horizontal shaft mounted in bearings in vertical standards, so as
to be capable of either endway or axial motion. This shaft at its inner
end is formed with two arms, one of them projecting downwards is borne
against and thrust forward by a piece of steel adjustable upon a hori-
zontal V slide. At the back of this slide is a bowle against which
bears the face of the traversing cam keyed on a supplementary cam
shaft driven by one of the train of spur wheels. Both the tool holder
and the V slide receive a backward inclination from spiral springs.
The other arm formed on the tool-holder shaft extends transversely back-
wards across the machine, and projects under the flange of a shaped
piece of steel termed a "former," which is mounted on the top of a vertical
V slide.
The upward and downward motions of this slide impart a
rocking motion to the tool holder shaft, and they are derived from a
face cam, and transmitted to the slide through a bell-crank lever and
link. This face cam is mounted loosely on a supplementary cam shaft
for the purpose of being slidden forward as each successive cut is per-
formed (bringing down the "former," and causing the tool to take a deeper
cut), and when the screw is finished drawn back to allow the tool.
holder shaft to rock sufficiently to throw it out of reach of the traversing
slide.
The position of this cam on the supplementary cam shaft is governed
in the following manner:-A transverse rock shaft mounted under-
neath the bed plate of the machine carries two levers, the shorter one
attached to the back of the sliding cam by a sliding coupling; the
longer arm bears against the face of a cam on the main cam shaft.
This cam has a gradually advancing action upon the longer lever,

page_text: traversing the cam on the supplementary shaft until the number of
successive cuts is complete, when the end of the lever falls into a
recess in the cam, whereby the tool holder shaft is removed from the
action of the traversing slide during one revolution to enable the
finished screw to be discharged, and a fresh blank to be placed in its
stead. The finished screw is received into a trough mounted on
trunnions, and made to advance at the proper moment to catch the
falling screw. From this trough it is discharged into a fixed trough,
and thence to a receiver. This arrangement effects the separation of
the screws from the cuttings which fall into a separate receiver.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Alfred Vincent Newton in the Great Seal Patent
Office on the 25th August 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
VINCENT NEWTON, of the Office for Patents, 66, Chancery Lane, in
tlie County of Middlesex, Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-fifth day of February, in the year of
our Lord One thousand eight hundred and seventy, in the thirty-third
year of Her reign, did, for Herself, Her heirs and successors," give
and grant unto me, the said Alfred Vincent Newton, Her special
licence, that I, the said Alfred Vincent Newton, my executors, adminis-
trators, and assigns, or such others as I, the said Alfred Vincent Newton,
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
"IMPROVEMENTS IN MACHINERY FOR MANUFACTURING SCREWS," being a com-
munication to me from abroad by Jared Augustus Ayres, of Hartford,
in the State of Connecticut, in the United States of America, upon the
condition (amongst others) that I, the said Alfred Vincent Newton, 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

page_text: carries also an elastic finger, between which and the edge of the segment
cap the blanks are severally received. By the rocking axial motion of
the cap the blank held between it and the finger will be carried down
to the axial line of the hollow mandril and deposited in a semicircular
groove formed in the face of the standard. The head of a sliding rod
mounted upon the boss of the cap is by this axial motion brought
between the prongs of a rocking lever, which being operated by a cam
will traverse forward the blank and thrust its head into the opened jaws
of the mandril. The mandril is mounted in bearings on standards and
provided with fast and loose driving pulleys for communicating motive
power to the machine. One end of the mandril is made hollow to receive
a pair of gripping jaws which are pivotted near their outer end, the other
extending inwards_and-terminating in a spring. Between the spring
-ends of these gripping jaws a wedge is thrust or withdrawn to cause
them to grip the head of the blank or disengage the finished screw.
The chasing tool holder is carried on a horizontal shaft mounted in
bearings in vertical standards, so as to be capable of receiving both an
endway and an axial motion. This shaft at its inner end is formed with
two arms, one of them projecting downwards and the other horizontally
and extending to the back of the machine. The pendent arm receives
motion from a screw cam which imparts a traverse motion to the tool
holder shaft, and the horizontal arm bears on the under side of a
"former," which is mounted on the top of a vertical V slide and imparts
a rocking motion to the tool holder shaft. The finished screw is received
into a rocking scoop which is made to advance at the proper moment to
catch the falling screw. From this scoop it is discharged into a fixed
shute, and thence to a receiver. This arrangements effects the separation
of the screws from the cuttings, which fall into a separate receiver.
Having now described generally the nature of the improvements I
will proceed to explain in detail the construction and working of the
machine.
In the accompanying Drawings Fig. 1 is a front elevation of the
improved screw threader; Fig. 2 is a plan view of the same; Fig. 3 is a
cross section taken at the line 1, 2, and in the direction of the arrow a,
and showing the construction of the hopper and the manner of
delivering the blanks in a horizontal position to the machine.
Fig. 4
is an elevation, partly in section, of the feeding end of the machine, the
feeding drum and its appliances being removed, shewing the means

page_text: employed for taking the blanks singly as they leave the vertical guide,
into which the hopper delivers them, and carrying them down and
thrusting them into the jaws which hold them while the chasing tool
is operating. . Figures 5, 6, and 7 are detached views explaining
some details of this part of the mechanism. Fig. 8 is a partial
longitudinal vertical section taken through the centre of the mandril.
Fig. 9 is a transverse section taken in the line 3, 4, and in the direction
of the arrow b. Fig. 1 shewing chiefly the means for actuating the
chasing tool shaft. Fig. 10 is a partial plan shewing also the parts
for actuating the chasing tool. Fig. 11 is a detached elevation of the
parts used for regulating the depth of cut of the chasing tool.
Referring now to the general views, Figures 1 and 2, A, A1, A2, A3,
A, A³, is the main framing of the machine consisting of a bed and
five standards; B is the mandril turning in bearings in the standards
A2, A3; C is the back or main cam shaft; D is the tool holder shaft;
E is a stud axle fixed to the standard A°, for carrying the rocking sleeve
and its appliances by which the screw blanks are carried down into
position. The rotary hopper is shewn at F (see also Fig. 3.) It
consists mainly of two conical shells secured together at their periphery
by transverse screws, and at such a distance apart as to leave a space
between them for the shanks of the blanks a to drop through and slide
as in a rotary guide. Within the shells are curved races f, f, (Fig. 3)
which extend from the periphery of the hopper inwards to meet a
curved guide F¹ (within the hopper) which receives the screw blanks
and leads them down towards the grippers, turning them from a vertical
to a horizontal position as before-mentioned, in order that they may
be carried to the grippers and presented thereto with their heads fore-
most. This guide F¹ is segment shaped at its lower end and it is
fitted with elastic guide pieces f¹, which prevent the blanks from
falling forward when running down the guide, and preserve them in
their descent in a proper position as shewn at Fig. 1. The blanks as,
they severally leave the guide F¹ fall on to the rounded head of the.
standard A, and in front of a segment shaped cap a¹ which rides over.
the rounded head of the standard. Each blank as it falls is. caught
and held firmly between the front edge of this cap and an elastic
finger a for the purpose to be presently explained. The cap piece a¹
and finger a are carried by the sleeve G which is mounted on the stud
axle E. The construction of this sleeve and the parts connected

page_text: therewith is best shewn in the detached views Figures 5, 6, and 7.
Projecting from the sleeve is an arm G¹ to which the finger a² is attached
by a clamping screw, and in such a manner that the forward end of the
finger lies parallel with the gripping edge of the cap piece a¹. A
sliding rod or plunger a³ is fitted to the sleeve for the purpose of
thrusting forward the screw blank a, when it has arrived opposite the
gripping jaws before-mentioned into the grip of those jaws. This rod
carries a boss or shoulder against which presses a spring a¹ (see Fig. 4,)
to keep the rod out of action, but when the sleeve (with its appliances)
is rocked to carry down the screw blank the rod will be embraced immc-
diately in rear of its shoulder by the notched extremity of a curved
oscillating bar H, which is mounted on a vertical fulcrum pin and
receives from that bar a forward motion in_its_bearings. Near-the
-termination of the curved head of the standard A®, a steel plate a³ is
inserted having a half round shaped groove formed in its face. This
is for the reception of the screw blank and it ranges in line with the
centre of the mandril B, which carries the gripping jaws. The notched
end of the oscillating bar H reaches therefore to and is moved in the
same plane, and it is to the same plane that the rocking of the sleeve
is required to bring and leave the screw blank.
I will now explain how the rocking of the sleeve Gand its appendages
is effected. In the sleeve casting (see Fig. 5), a radial slot is formed to
receive a sliding block or driver. This driver is jointed to a compound
rock lever g, g, which has for its fulcrum a stud pin g on the standard
A. The part g₁ of the compound lever carries a steel pin which is
acted upon by a tappet cam g³ mounted on the back or cam shaft C.
At every rotation therefore of this shaft the cam g³ will strike the pin
of the compound rock lever, depressing its rear end and lifting its
forward end and the sliding block or driver which it carries, and thus
move the sleeve on its axis until the segment cap and elastic finger
have carried down the screw blank opposite the groove in the face of
the standard A. The finger a will then thrust the blank into the
groove and hold it there for a moment. While the sleeve is held at rest
in this forward position by its cam g³, a tappet h projecting from the
side of the camı g³ will strike the tail of the curved bar H, causing its
notched end to move inwards and thrust forward the blank (head fore-
most) into the gripping jaws now open to receive it. This being done,
the oscillating bar and the sleeve will be released by their respective

page_text: tappets or cams having passed out of action, and by means of coiled
springs g the sleeve and its appendages will be returned to their normal
position, while the bar His thrust back by the spring a' of the plunger
a³. I have described the rock lever g, g', as a compound lever, because
it is composed of two [parts g, g', which, are connected together by a
spring coiled round the stud pin g², the ends of the spring being caught
by stop pins, as shewn at Fig. 4. The object of thus constructing
the lever is to allow of its giving an clastic pressure, and to provide a
means of neutralizing the jar which may occur at the arrest of the
downward motion of the cap piece a¹. The springs g* are connected to
the rock lever by a swivel piece 9, their other ends being hooked to a
pin on the back standard A*.
I will now proceed to explain the construction of the gripping jaws
and means of operating them, so that they may firmly hold the screw
blank and give axial motion thereto while under the action of the
chasing tool, and then discharge it when the thread is formed on
the
blank.
T
The mandril B is made hollow at its inner end (see Fig. 8,) to receive
a pair of gripping levers b, which are fitted with steel jaws 6', 6'. These
levers are pivotted at 62, and are formed with clastic terminations b³, b³,
which serve to modify the pressure of the jaws upon the screw blanks.
The tail ends of the levers are tapered to admit of the insertion between
them of a wedge-shaped projection &, formed on a sliding block 5,
which is secured by pins to a sleeve Uº. This sleeve embraces the
mandril B, and slides upon it with the block which it carries. To allow
of this the mandril is slotted through and forms a guide for the block,
ensuring at the same time the rotation of the sleeve with the mandril.
On the sleeve 6 is formed a collar which is enclosed in a box that is
fitted with trunnions. These trunnions are embraced by the forked termina-
tion of a cranked lever 68, which has its fulcrum at 6º (see the plan view
Fig. 2,) and is intended to operate the wedge-shaped projection and cause
it to close the gripping jaws on the screw blank. The crank lever is
itself operated by cam surfaces carried (see Fig. 9) by the spur wheel (B³)
through a pin 6 which it carries; but to provide against the rocking
lever 6 affecting the position at which the pin is presented to the cam
surfaces this pin is made fast to the head of a lever 6" which rocks
on a fixed fulcrum at 6. A spherical projection is formed on this pin,
and it is embraced by the termination of the rock lever, so as to form

page_text: a ball-and-socket joint. It will now be understood that as the spur.
wheel B is rotated in the direction of the arrow, Fig. 9, the cam
surfaces which it carries will through the pin 610 rock the lever, and
cause the sliding block 65 to advance and recede as required, thereby
closing the jaws on the screw blank, and holding it fast while the
chasing tool is operating and releasing the pressure, and allowing them
to open under the action of springs *; *, to release the work. Between
the jaws is a thin steel bar 6* which is intended to take into the nick
of the screw blank, and effectually prevent its turning in the jaws under
the pressure of the chasing tool. This bar is carried by two parallel
sliding pins which enter holes made for them in the end of the mandril,
and have a forward pressure imparted to them_by_coiled-springs-placed
at their rear ends. If therefore the blank is presented to the jaws with
its nick across the bar 6* the bar will be forced back by the thrust
given to the blank by the plunger a before mentioned, but a partial
rotation of the mandril will bring the bar into line with the nick, and it
will then enter the nick, and remain there until the screw is finished
and discharged from the machine.
The progress of the screw blank having been traced from the hopper
to the jaws which rotate it in front of the chasing tool, I will now
explain the means whereby this tool is traversed again and again from
the head to the point of the screw blank, deepening its cut at every
traverse, and advanced suddenly forwards at the point, so as to cut a
thread thereon.
d is the chasing tool carried by and adjustable in a tool holder D¹,
which is made fast by a clamping screw to the tool holder shaft D. The
traverse of the tool along the screw is derived from the traverse or
endway motion of the shaft in its bearings A¹, A³. The inner end of
this shaft terminates in a horizontal arm d', which is fitted at its
extremity with a steel plate & that bears upon and slides over the face
of an inverted "former" D² (see Fig. 8). This "former" by rocking
the shaft D gives the sudden dip to the tool to cut the thread on the
point of the screw, and it also receives as will be. hereafter explained
a progressive downward motion whereby at every succeeding traverse
of the tool over the screw it causes it to cut deeper into the shank
until the thread is finished. Pendent from the shoulder of the arm d'
is a steel plate which is intended to receive the thrust of a screw
cam D provided for giving the forward endway motion to the tool

page_text: holder shaft D. The return motion is given to this shaft by an inclined
coiled spring d which is so arranged as to rock the shaft in its bearings
to throw the tool back from its work when it is no longer held thereto
by the "former" D. The screw cam Ds is carried by a horizontal shaft D*
and turns in bearings in the standards A², A³. This cam represents one
turn of a screw thread nearly completed and its ends connected by an
abrupt incline. On the face of this cam works a pin № carried by a
horizontal slide which works in a V guide in the face of a block A'
secured to the bed of the machine. The pin of this slide is held against
the cam by a coiled spring d³, and the end of the slide is propelled by
the cam against the steel plate of the tool shaft arm.
At every
rotation therefore of the cam D³ the chasing tool is caused to traverse
over the screw blank, but as the cam completes a rotation its abrupt
incline will be brought opposite the pin of the slide and the coiled spring
being allowed to contract it will draw back the slide do, and releasing
the arm d from its pressure the shaft D will be free to return (under the
action of its spring d*) to its starting position. Supposing now this
forward endway motion of the tool shaft to be repeated, the arm d'
traversing under the former" D° will be controlled in its traverse,
"
dipping as the "former curves downwards and thus throwing the tool
nearer the axis of the screw. Again as the former is gradually
depressed the movement inwards of the tool will correspond to that
depression.
I will now explain the means whereby the former is actuated, so as
to advance the tool gradually towards its work, and suddenly to release
it at the end of every traverse. The former D2 is mounted or forms part
of a vertical slide, which receives a tendency to rise from the upward
pressure of a spring d³. Connected to this slide by a link and screw d
is a bell-crank lever d, which has for its fulcrum a pin carried by the
fixed framing. The raised arm of this lever carries a pin ", which
bears against the face of a disc plate D³, mounted on the shaft D*. This
plate is fitted to slide upon and rotate with its shaft, and its face is
furnished with a notch, which when presented to the pin of the crank
lever will allow that lever to rock under the upward pressure of the
spring d³, and in so doing give the former (whose upward movement
is restrained) freedom to rise sufficiently to allow the tool holder shaft to
rock under the action of its spring and thus throw back the tool clear
of the work preparatory to its rapid return (also effected by the same

page_text: spring); to take up again its starting position. By reference to Fig. 8
it will be seen that in proportion as the disc plate D³ is pressed forward
in the direction of the arrow, so will the former D³ be depressed and
the chasing tool be set further in to produce a deeper cut. It remains
however to show how a continuous forward motion is given to this disc
plate. This is effected by means of a face cam D, mounted on the cam
shaft C which rotates once during the threading of a screw. The face
of this cam D (see Fig. 11) is a gradual inclined plane terminating in a
deep recess with an inclined side, and against it bears the hooked end
of a compound arm D³, D³, the parts being connected together by a
spring to give the arm a yielding power. The lower part of this arm
is cast with an elongated boss or shaft which at its opposite end carries
an arm D, and this shaft is mounted on screwed centres da and is
capable of rocking thereon. The arm D³ carries a disc d¹³ which is free
to turn on its stud axle, and the face of this disc bears against the back
of the disc plate D³. The pressure of this disc d¹³ it will be understood.
is maintained by the cam D° acting on the arm D', but when the deep
recess of the cam is brought round, the arm D' will fall into it and
thereby rock its shaft, which will throw, back the arm D and relieve
the disc plate D³ of the pressure of the disc d¹³. Immediately this
pressure is removed the former D³ will be lifted, and will through the
crank connection force back the disc plate D5 on its shaft, beyond
the position from which it advanced at the commencement of the
threading of the screw. The backward traverse of the disc plate D³
releases the former, and allows it to rise to its highest position to be
ready for the re-commencement of the chasing operation on a fresh
screw blank, the rise of the former giving as before explained the
opportunity for the chasing tool to travel back to its starting position.
On the cam De repeating its pressure on the lever D', after a sufficient
pause to allow for the delivery of the finished screw, and the insertion
of a new screw blank into the gripping jaws, the disc d¹ will again
advance and press forward the disc plate D³ into position for ensuring
the repetition action of the chasing tool. When the screw is finished
the sleeve is drawn back by the oscillation of the forked lever 68, and
the wedge projection 7 of the sliding block 65, being thereby withdrawn
from the gripping levers B they will release their hold of the screw
and allow it to fall. At this moment a scoop-shaped rocking piece I'
advances to receive the falling screw, and guide it down to a shute
which conveys it into a suitable receptacle below. This shute is shown

page_text: at I, Fig. 1, as fixed to the framing and the rocking scoop I', which is
set above it is carried by a transverse rock shaft I, (Fig. 2), which
is mounted in lugs secured to the bed of the machine. The back end
of this shaft is fitted with a short arm i, shewn detached at Fig. 12,
Sheet 2, which is operated upon by a wiper also shewn detached
at (Figures 13 and 14, Sheet 2) affixed to the cam shaft C. As this
shaft rotates once only during the threading of a screw, the wiper ¿¹ will
come into action the moment the screw is released, and thereby throw
forward the scoop, bringing it under the jaws to receive the falling
screw. A second fixed shute I³ is provided for receiving the cuttings
that drip from the lubricator, and guiding the same into a suitable
receptacle. When the screw has been caught by the scoop and discharged
from the machine, a spring will return the scoop to its former position,
as shewn in Fig. 1.
The manner of timing the several operations above enumerated will be
readily understood by reference to Figures 1, 2, and 9, which shew the
mode of gearing the mandril B and the cam shafts C and D'. The
mandril carries the fast and loose belt pullies B¹, and secured to its outer
is a pinion B³. Into this pinion gears a spur wheel B³ which carries
a pinion B' in gear with a spur wheel B secured to the end of the shaft
D' and thereby imparts rotary motion-to. that shaft. A pinion B on
this shaft drives the large spur wheel B' on the cam shaft C through the
mediation of a pair of spur pinions B³, thereby imparting to that shaft a
slow rotary motion as above described. It may here be remarked that
the relative speeds of the shafts B, C, and D' may be changed to suit
different pitches of screw and to vary when desired the number of cuts
made by the chasing tool in forming the thread. A slow rotary motion is
imparted to the hopper in the following manner :-On one of the conical
shells of the hopper F is formed a ring of ratchet teeth f¹ into which
takes a weighted pawl ƒ (Figures 2 and 3). This pawl is pivotted on a
weighted radius rod F² which rocks on the stud axle of the hopper.
its weighted end this rod is fitted with a pin f³ which rides on a star
wheel F made fast to the cam shaft C. As therefore this shaft is
rotated the star wheel will present a series of inclines to the pin of the
weighted lever and thus alternately lift the lever and allow it to return
to the position shewn in the Drawing. The effect of the pin f³ thus
riding on the star wheel will be to cause the pawl få alternately to drive
the hopper round the distance of one or more teeth and to slide back to
At

page_text: repeat the action. Thus the hopper will receive a slow rotary motion
and the screw blanks thrown promiscously into the hopper will thereby
be caused to arrange themselves on the races f and slide down the
guide F¹, as already explained, when the races are severally brought into
line with the fixed guide; f' is a second weighted pawl for pre-
venting the running back of the hopper during the return stroke of the
pawl f*.
Having now set forth the nature of the Invention of "improvements
in machinery for manufacturing screws as communicated to me by my
foreign correspondent, and explained the manner of carrying the same 1
into effect, I wish it to be understood that under_the_above-in-part
recited Letters Patent-I-claim,
First. The arrangement above described for conveying the headed
screw blanks one by one to the rotating gripping jaws.
Secondly. The arrangement of gripping apparatus applied to the 1
mandril and operated as and for the purpose above described.
Thirdly. The arrangement above described for traversing and rocking
the chasing tool and governing its action as the work of threading the
screw blanks advances.
Fourthly. In combination with the above the rocking scoop operated 2
as above described for delivering the finished screws out of the
machine.
In witness whereof, I, the said Alfred Vincent Newton, have here-
unto set my hand and seal, the Twenty-fifth day of August,
in the year of our Lord One thousand eight hundred and 2
seventy.