IMPROVEMENTS IN AUTOMATIC LATHES FOR CUTTING SCREW- THREADS AND FOR OTHER PURPOSES
Year: 1882

page_text: LETTERS PATENT to Frank Wirth of the Firm of Wirth and Company Patent
Solicitors at Frankfort-on-the Main, in the Empire of Germany, for an Invon.
tion of "IMPROVEMENTS IN AUTOMATIC LATHES FOR CUTTING SCREW-
THREADS AND FOR OTHER PURPOSES." A communication from Georg Heyne
and Ernst Heyne trading under the Firm of Heyne Brothers of Offenbach on
the Main, Germany
PROVISIONAL SPECIFICATION left by the said Frank Wirth at the Office of
the Commissioners of Patonts on the 27th January 1882.
FRANK WIRTH of the Firm of Wirth and Company, Patent Solicitors, at
Frankfort-on-the-Main in the Empire of Germany "IMPROVEMENTS IN AUTOMATIC
LATHES FOR CUTTING SCREW-THREADS AND FOR OTHER PURPOSES. [A communi-
cation from Georg Heyne and Ernst Heyne trading under the Firm of Heyne
Brothers of Offenbach on the Main, Germany.]
This Invention relates to an improved lathe or machine for cutting screw
threads for the manufacture of screws, boring metal, and for other turning
operations. The said machine is constructed and arranged as hereinafter set
forth.
Upon an iron-bed plate I arrange two parallel shafts supported at each end by
bearing blocks and upon one end of each shaft there is a worm-wheel. For the
purpose of explanation I will denominate one of the shafts No. 1 and the other
No. 2; upon the shaft No. 1 I provide four cams and upon the shaft No. 2 five
cams. The periphery of three of the cams is grooved, the grooves deviating into
one or more lateral curves. Upon two of the cams there are projecting bevelled
pieces and two of the other cams are provided each with a ring whose dimensions
increase gradually from a certain point so as to form a projection. On one of the
cams on shaft No. 1 there is a projecting excentric piece and on a corresponding
cam on shaft No. 2.there is a projection in the form of the segment of a circle. In
a central position between the aforesaid shafts, and somewhat higher than the
latter, I provide another shaft having suitable bearings. Upon this central shaft,
and free to move around the same, I provide three cone-pulleys in different
positions. Two of these pulleys are placed near one end of the shaft and between

page_text: The
them the shaft is surrounded by a square piece which is fast thereto. At the
other end this shaft is provided with a chuck which is movable longitudinally.
At the same end this shaft is provided with two slots intersecting each other at
right angles and in each of these slots are two wedge-shaped pieces. The front
part of the chuck is surrounded by a ring in which there are, over the slots,
thumb-screws for operating the wedge shaped pieces. At the front, the chuck is
covered by a disc screwed thereto, which has in its centre only, an opening equal in
size to that of the shaft. At the rear, the periphery of the chuck is provided with
a groove which is about two centimetres in depth, and three centimetres in width.
Two rings or blocks on tho said central shaft are provided with a similar groove
in their periphery and are fitted to be moved to the right and to the left upon the
shaft. At the point on the shaft at which these two rings are situated the said
shaft is cut through so that a slot is provided in which two claws are so arranged
as to be movable vertically. These claws are jointed, in two slits, provided in one
of the said rings, by means of a pin that passes completely through the same.
other ring is conically shaped on one side so that, when it is pushed towards the
first named ring, the outer arms of the claws will be pressed towards one another,
whilst the ends of the claws which are in the slot in the shaft are pressed together.
Another ring upon this spindle has three levers jointed thereto. With the
respective extremities of these levers, each piece of a brake composed of three parts
is connected, also by means of a joint. On the inner side of these pieces, strong
leather is screwed. There is a fourth ring on this central shaft and which is
movable; it is of conical shape on the side next to the brake. When this ring it is
forced towards the brake the lever arms are, through its conical part, pressed
upwards whereby the brake-pieces are pressed firmly against the cylindrical parts
of the third cone-pulley. As three-lover ring is fast upon the shaft, this cone-
pulley is held securely with the shaft and the two therefore turn around together.
On the aforesaid square piece there is a ring, which is also provided with a groove
and is movable towards either side. Upon this, as also upon both the two end
core-pulleys, catches are provided. All the parts which have the grooves are
connected by levers with some of the other cams. One lever is bifurcated at its
upper end and the ends of the fork, are provided with small rollers, whose thickness
and length correspond with the size of the groove in which they engage. At the
lower part of this lever there is likewise a roller which runs on the curves and
between the bevelled pieces of the cams. The lever can turn round a screw which
serves as its axis. If therefore, the said lever is shifted by the curved or bevelled
pieces of the corresponding cam, the movement is transmitted through it, to the
corresponding ring or piece placed upon the shaft. There is a slight carriage
movable back and forth upon the bed, and when it is shifted forward it is brought
back by spiral springs lying underneath. In the puppet there is a socket in
which, surrounded by a spiral spring, there is a bolt to which is screwed the cutting
apparatus and which can be moved longitudinally but cannot revolve. When
therefore a lever provided for the purpose is shifted forward by another lever, as
soon as the pressure of the said lever ceases, it is brought back to its original
position by the spiral springs. On the fore part of the chariot, the cutting
apparatus is arranged by means of a joint; the cutting tools are screwed thereon.
On an axle placed at a right angle to the other shafts are arranged two worms
whose thread run in opposite directions and which gears with the teeth of the
worm-wheels on the two parallel shafts whereby these wheels are caused to revolve.
The cone-pulleys are connected with the same by means of cords on thin leather
bands. The cord upon two of these pulleys is crossed, so that these pulleys revolvo
in a direction inverse to that of one of the others. Moreover the cone pulley near
the chuck is caused to revolve much more quickly than the two end pulleys. The
central shaft is hollow and receives the wire or rod to be screw threaded which
wire or rod is drawn straight, and so long as it is not taken up from the shaft, rests
in a particular guiding position. The machine being then set in motion all the
necessary operations for adjusting the length to which the wire or rod is to bo

page_text: screw threaded or cut so as to form scrows of different length may be readily made
so that the work will be effected automatically and with great accuracy.
If the work to be accomplished does not require the cutting of a screw-thrend,
the right and left hand motions are not needed, consequently the mechanism for
effecting this motion is not required.
When, instead of making screws, it is required to boro sockets, or the like, in
place of a scrow cutting apparatus, a borer has to be secured to the bolt and the
cam or disc at that end of shaft No. 1 is provided with a bevelled covering. Many
different objects may be turned by this machine by changing the cams and the
cutting apparatus in a suitable manner which will be readily understood without
further description; all these objects can be produced by this automatic machine
in a most accurate manner.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Frank Wirth in the Great Seal Patent Office on the 27th July
1882.
FRANK WIRTH, of the Firm of Wirth & Company, Patent Solicitors, at Frankfort-
on-the-Main, in the Empire of Germany, "IMPROVEMENTS IN AUTOMATIC LATHES
FOR CUTTING SCREW-THREADS AND FOR OTHER PURPOSES." A communication
from Georg Heyne and Ernst Heyne, trading under the Firm of Heyne Brothers,
persons resident at Offenbach-on-the-Main, Germany,
This Invention relates to an improved lathe or machine for the manufacture of
screws for boring metal and for other turning operations.
In the accompanying Drawings
Figure 1 is a plan of a screw cutting boring and turning lathe constructed
according to this Invention.
Figure 2 is an end elovation of the same.
Figures 3 to 17 are detail views.
Like letters indicate the same parts throughout the Drawings.
Upon an iron bed plate I arrango two parallel shafts D' D" supported by bearing
blocks L and upon one end of each shaft there is fixed a worm wheel R¹ R'.
Upon the shaft D' I arrange four cams A, B, C, and I one of them C having a
groove as shown in Figure 10, the other three having projections as in Figures 4,
11, 12, and upon the other shaft D" five cams are fastened two of which E and G
have grooves as in Figures 14, and 15, and the other three D, K, and F projections
as in Figures 4, 13 and 17.
In a central position between the shafts D' D" but somewhat higher I provide
a hollow shaft E having bearings L' L. Upon this shaft and free to move around
it are three cone pulleys P, P¹, and P". Between the pulleys P¹, P", Figure 1 I

page_text: place a square sleeve W securely fitted to the shaft E¹. At the other end of this
shaft and movable longitudinally upon it is the chuck Q the construction of which
is represented in Figures 5 and 6. At the end of the shaft E¹ two slots intersect
each other at right angles and in each of these slots are two wedge-shaped
pieces,, having their inclined faces together. The front part of the chuck is
composed of a ring in which are thumb-screws for operating the wedge-shaped
piecesz, ; inside this ring a disc or cover is fixed, having in its centre a hole
equal in size to the hollow of the shaft E¹, the rear part of the chuck is provided
with a groove about two centimetres in depth and three centimetres in width.
Two rings or blocks R, and S which are also on the shaft E¹ are grooved in a
similar manner for the purpose of moving them longitudinally upon the said shaft.
At the point where these two rings are situated a slot is cut through the shaft and
two clawek, k, pivotted to the block S are so arranged that when the block R
which has a conical face is pushed towards the block S the inner ends are pressed
together into the slot. Another ring T is fastened to the shaft E' and to it are
jointed three levers (Figures 1 and 5) each of which carries a block of the
brake u which is divided into three sections, the inner side of each of these sections
is lined with strong leather secured in some suitable manner. The ring V is
movable longitudinally upon the shaft, and when its conical face is forced towards
the levers the brake pieces u are pressed firmly against the cylindrical boss of
the cone pulley P and as the ring T is fast upon the shaft the cone pulley P is
held securely with it and the two therefore turn around together. On the sleeve W
and free to slide upon it is the ring H which is grooved in a similar manner to S,
upon the ring H and also upon the inside faces of the cone pulleys P', P", are
catches a, a, a, and a". "All the rings or blocks Q, R, S, V, and H which have
grooves are connected by the levers y, y¹, y", with the cams E, F, B, G, and C
respectively. All the levers y, y¹, y¹, are bifurcated at their upper ends as in
Figure 9 and the ends of the forks are severally provided with small rollers whose
dimensions correspond with the size of the grooves in which they engago. - Each
of these levers has likewise a roller at its lower end which runs in the grooves and
between the projections of the different cams, these levers are also free to move
If
laterally upon pivots m which are attached to the bed-plate by an arm.
therefore one of these levers is moved by the corresponding cam, this movement is
transmitted to the ring or block placed upon the shaft E' which is in connection
with it. Upon the bed B₁ there is a slide-rest M (Figures 1, 3, and 4) having
spiral springs e beneath it so that it will be drawn back after the cam A has pushed
it forward and released it. In the head O there is a socket N (Figures 1 and 3)
having an internal spiral spring; inside this spring and socket and capable of
longitudinal movement only is a bolt to which is attached the screwing
apparatus S¹. When therefore the bolt b¹¹ is moved forward by the lever Z as
soon as the pressure of the said lever ceases, it is brought back to its original
position by the spiral spring. On the fore part of the saddle or slide rest M the
arms bb' are attached as shewn in Figure 4 by means of joints these arms carry
the tools g, g¹. On the axle A¹ lying at right angles to the centre spindle are two
worms having their threads cut in opposite directions and engaging with the
wheels R R' on the shafts D¹ D", whereby these wheels R R' are caused to revolve
in opposite directions as indicated by the arrows in Figure 2. The cone pulleys P
Pipi and P are driven from a common shaft by means of cords or thin leather
belts. The belts upon the two pulleys P, P¹, are crossed in the same manner so
that they may revolve in a direction reverse to that of the pulley Pl, the cone
pulley P being connected with a large pulley on the driving shaft is caused to
revolve much more rapidly than the pulleys P¹ P¹¹. The speed of the shaft E¹ is
different from that of the shafts D¹ Du
I will now proceed to describe the action of the machine. In the hollow shaft E
is placed a piece of wire or rod which is to be made into screws, the wire must be
perfectly straight and have its extra length outside the machine suitably supported.
The machine being set in motion, the projections on the cam Fact on the lever

page_text: and move it to the left, the consequence of which is that the ring R upon the
spindle E is moved to the right, its conical face being pressed between the
levers k, l, and forcing them outwards, whereby their lower extremities come
together and clip the wire which is in the said spindle. When this has happened
the lever y¹ is moved by the cam B and thereby the ring S and the ring R,
together with the wire held fast by the claws are pressed forward a certain
distance, which distance can be very accurately regulated to suit the length of the
screws it is desired to cut, by altering the position of the cam on the shaft D'.
When the lever y¹ has passed the projection 9 (Figure 11) of the cam B, the wire
has then been pushed through the desired length, then the chuck Q is shifted from
left to right by means of the grooves in the cam E acting upon the lever yll whereby
the wedge-shaped pieces z, 21, press firmly upon the wire (Figure 5) so that it can
move neither forwards nor backwards, nor turn independently of the shaft.
Through the shifting of the blocks R and S which follows from the cam having
turned to another position the claws k, k, relinquish their hold upon the wire, the
projection of the cam K now acts upon the rod of the turning apparatus b₁
(Figures 1 and 4) and thereby the chisel or tool g¹ is brought to bear against the
wire, in position for turning at the same time the slide rest M, through the face of
the cam D pressing against the rod i" (Figure 1) is shifted forward, and with it the
turning tool g' theroto affixed, the wire will thus be regularly turned for a certain
length which is regulated by the bevelled parts of the cam D, and the elevation of
the segment of the cam K. The spindle E¹ is set in motion by the wheel P
alone, on account of the conical part of the ring V (Figure 1) being pressed under
the lever arms, 1, of the brake u. The ring E, upon the sloeve W stands midway
between the wheels P' and P" and its catches do not come in contact with those
of the wheels P¹ and P" but when the wire has been turned as aforesaid and the
ring V is shifted from left to right by the cam G, (Figure 1) the brake u is loosened,
and the wheel P revolves freely round the shaft, then the ring H on the sleeve W
is shifted from right to left by the cam C so that the catch a¹ of the ring H comes
into contact with the catch a of the wheel P' and thereby the shaft E¹ is set in
motion but slower than before, because the speed of the wheel P is not so great
as that of the whcel P. Through the cam A (Figure 1) the lever Z is pressed
against the bolt 6 which is in the socket N whereby the screw cutting dies 8¹
which are placed at the fore part of the socket are brought up to the wire which is
rotating. When two threads have been cut in the wire, the screwing apparatus,
which together with the bolt is movable in the socket N and is only held in
position by means of a strong spiral spring, is drawn forward until the screw is
cut to the required length. When this is comploted the spindle E' will
momentarily cease to work, through the ring H being shifted from left to right, by
the cam C; by a further shifting to the right, the catch all of the ring H, comes
into contact with the catch a of the cone pulley P", and the shaft E begins to
rotate in a contrary direction and the cut screw is thus drawn out of the
screwing apparatus & which is then drawn back by the spiral springs into the
socket N; the projection ul of the cam I now comes into contact with the rod i
(Figure 4) raising the arm b and pressing the chisel or tool g against the wire, a
certain distance (which can be adjusted to the length required) from the screw
thread, severs the screw from the wire or rod through the tool constantly being
brought more forcibly against it by the cam I. When this has happened, the parts
all return to the position in which they were at the beginning of the operation
just described, and the said operation is repeated so long as there is wire.
When instead of making screws it is required to bore sockets, or the like instead
of a screw cutting apparatus, a boring tool has to be secured to the bolt in the
socket N and the cam A has to be provided with a bevelled covering H' to alter
its shape as represented in Figure 16. Many different articles may be turned by
this machine such as discs, buttons and the like by changing the cams and the
cutting apparatus in a suitable manner which will be readily understood without
further description; all articles produced by this automatic machine are finished in

page_text: a most accurate manner. If the work to be accomplished does not require the
cutting of a screw thread, reverse motions of the pulleys P P are not necessary,
consequently the mechanism in connection with this motion is not required and
the turning lathe may move continuously in one direction.
Having thus fully described the said Invention and the manner of performing
the same I wish it understood that I claim,
First. In an automatic lathe for turning or boring hollow or round bodies, such
as sockets, buttons, and the like, the hollow spindle E' in combination with the
chuck Q, the conical shaped ring R, the ring S with the claws k, the cone pulley P
with or without the brake apparatus consisting of the parts uT, and V, the
shafts D D with the cams fixed thereon the worm-wheels R¹ R¹, the shaft A'
baving the right and left handed screw-threads, the lever Z and the slide rest M,
the cutting devices movable upon joints; the head O, with the socket N, and the
bolt therein, surrounded by a spiral spring, and provided in the front
part with either a screwing or a boring tool, substantially as described and for the
purpose specified.
Second. In a lathe for cutting screw-threads, the mechanism above described, in
combination with the cone-pulleys P P adapted to be rotated in one or the other
direction, the ring H, the cam C, the brake u and the cam G substantially as
described and for the purpose specified.
In witness whereof I the said Frank Wirth have hereunto set my hand and
seal this Twenty fourth day of July in tho year of our Lord One thousand
eight hundred and eighty two.