Year: 1896

page_text: Co., or Verikon, Switzerland.
1, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors, 322, High Holboru, in the County of Middlesex,
6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both in the County
of Lancaster, and Lower Temple Street, Birmingham, in the County of Warwick,
Civil Engineer, do hereby declare the nature of this invention, and in what manner
the same is to be performed to be particularly described and ascertained in and by
the following statement :-
The present invention has for its object an automatic screw cutting machine, in
which the advance of the work, the support of the shaping tools and the backwards
and forwards motion of the support table with the tools as well as the backwards
and forwards motion of the screw cutting mechanism is effected completely
automatically by means of suitably arranged mechanisms in combination with
reversing gearing. Moreover there are provided in the machine adjusting
mechanisms working entirely independently of one another for the shaping, the
cutting out of the screw, the screw thread cutting and the moving of the work,
which motions are controlled by the employment of adjustable wheel gearing and
adjustable cams or dises in order to make the length of the course of the working
organs always correspond to the measurements of the kind of screw then to be
made. In this machine moreover the driving mechanisms for the lathe and for the
screw cutting tool are arranged to work separately from one another and inter-
changeably in order to render possible the insertion of wheels for the purpose of
altering the speed, in such manner that in the machine together with the length of
the stroke, the speed also of the working organs can be altered corresponding to
the size and strength of the screws.
In the accompanying drawings illustrating the invention by way of example
Figure 1 is a front view partly in section of the machine;"
Figure 2 is a back view of the same;
Figure 3 is an end elevation viewed from the right;
Figure 4 is a vertical cross section on the line -x of Figure 1;
Figure 5 is a vertical cross section on the line y-y of the same figure;
Figure 6 is an end elevation viewed from the left, the advancing mechanism for
the work being left out;
Figure 7 is a detail.
A is the support carrying the shaping tools, which as previously indicated receives
its horizontal motion parallel with the work from the common driving gear of the
reversing mechanism (namely the stepped cone a upon the shaft a°) by means of
suitable intermediate mechanism. Upon the shaft a° are placed two lose worms
of which the one a¹ as soon as the support is to be pushed to the left for the
purpose of shaping the work, comes in gear with the coupling muff g keyed
adjustably upon the shaft, in such manner that it revolves with the latter and so
shares the rotation of the shaft aº.
The worm a' acts upon a gear wheel a² and from this the motion is transferred
through gearing a³ at as a to the eccentric a' fixed upon the cross shaft as which

page_text: forms the actuating organ for the adjustment of the support when the screw is
being shaped.
The periphery of this eccentric is formed in the shape of a snail cam having a
sharp heel surface which is directed radially, and forms the descent from the highest
point of the eccentric to the lowest point. The support frame A has on one side
a projecting piece a resting upon the surface of the ercentric a' and is pressed
with the latter firmly against the eccentric by the pressure of a spring .
When the support has arrived at its furthest position to the left, and consequently
the shaping of the work is just finished, the heel surface of the eccentric will have
come under the projection of the support. The projection has then passed the
highest point of the eccentric, and the support will in the next moment under the
pressure of the spring fly back into its original position to the right. This moment
(that is the position of the parts at this moment) is shown in the drawing. Beside
the support A a two armed tool holder A is pivotally attached to a piece a10
arranged upon the cheeks of the bed, the upper arm of which tool holder carries a
cutting tool. The lower arm of this tool holder is provided with a roller all which
lies upon a shaped piece a" secured upon the supporting table A. When the
support moves to the left the roller all on this shaping piece a slides upwards,
the head of the holder enrrying the tool will sink, and the tool will groove or partly
cut off the work in the proper manner on the top of the screw head to the same
depth as the shaper has cut the screw shank on the other side of the head. The
position of the roller upon the highest point of the forming piece corresponds to the
left position of the support shown in the drawing. The work is thus partly cut
off, and with the springing back of the support into its right side commencing
position, the roller of the pivoted tool holder, will roll down the surface of the
forming piece, and the other arm of the tool holder correspondingly rise so that
the tool is drawn away from the work the partly formed screw heing still connected
to the work by a neck having the diameter of the screw shank. The bringing
forward of the supporting table A' with the shaping tools to the work into the
working position, that is the shifting of the table A at a right angle to the notion
of the whole support is effected by means of a two armed lever 6 which is hung
between the cheeks of the support and has a toothed segment on its upper arm
which engages in a corresponding rack on the lower surface of the adjustable table.
The lever 67 lies with its lower arm against the edge of a disc fixed upon
the shaft 3, and which has a recess 6. Into this recess the arm slips as soon
as the shaping tool has finished its cut, that is when the support A is in the position
shown in the drawing as clearly shown in Figure 5. In this figure, corresponding
to the position of the other parts, the disc & is in such a position that at the next
moment the arm & will slip into the recess whereupon a spiral spring fixed in
the supporting table can spring the latter back, the recess in the disc allowing the
lever so much play that it can make the corresponding movement.
The shaping tool will consequently be drawn away from the work until the
recess has passed the lever arm 6 whereupon in consequence of the arm again
slipping over the full surface of the eccentric the lever makes the opposite motion,
whereby its upper end again advances the supporting table. The shaft bearing
the disc is driven by means of bevel wheel gearing from the shaft a³ (see
Figure 4).
The disc is of course adjustably fixed upon the shaft 2 so that it can be carried
along by the support A in its movement to and fro. The movable support A has
opposite to it a fixed support B which carries the parting tool, the table B' of
which support B is movable in a similar manner to the table A' of the support A
at a right angle to the work. In order to effect this displacement there is provided
a double lever c2 c3 which is actuated by means of a tappet c¹ fixed upon the shaft c
and behind which the lower arm c2 engages, whilst the upper arm chas a toothed
segment which works in a corresponding rack on the under surface of the table B.
In Figure 5 the lever and the tappet e stand in such a position that in the
next moment the latter will give to the former a motion causing the advance of the

page_text: abre is
provided win
CA
the position shown in Figure 5 as soon as the parting is accomplished and the
tappet el has passed the lever e
The shaft c receives its motion from the worm d by means of gearing d¹ d² d³ d
d de d as soon as the coupling muff g fixed upon the shaft a has been moved to the
left, out of the position shown in the drawing, and the end thereof has been
brought into gear with the clutch disc g' attached to the worm d whereby the
worm al is disconnected and d connected."
It is moreover obvious that this disconnection of the worm al and the connecting
of the worm d can only then take place after the screw has been shaped and the
parting tool as well as other mechanisms to be hereinafter described which
disengage the apparatus for the turning of the head and effect the movement of the
work and limit it, have been set in motion. The displacement of the coupling
muff g is effected by means of connection yg under spring pressure with whose
lower arm g3 a fork g surrounding the muff is connected. The moving of this
connection to the right or to the left is effected by means of a guide rod 9 which
engages in a slot of the lever g³ and which has two notches g7 g8, placed each close
to one end of it respectively, in which the claws of two discs go go can engage. As
soon as the disc g10 upon the shaft as has pushed the bar to the right in the manner
shown in the drawing, the connection, whose upper bar g is mounted in a guide
pivotally attached to the frame, will strike out in the same direction whereby the
muff g is pushed to the left by the fork g and the coupling of the worm d with the
shaft a is effected.
When the working process is ended, that is when the screw is cut, the finished
screw is cut off or discharged and the work is again pushed forward; the disc g
then comes into action which engaging with its finger in the notch a pushes the
bar to the left, in consequence of which the connection 93 strikes to the left,
whereby the muff g is pushed to the right and the worm a is again so connected
with the shaft a that the shaping can take place. As already stated, the disc g
which causes the engagement of the worm d is fixed upon the shaft a which
consequently receives its motion from the worm a' through the intermediate gear a²
to a'. The disc g' which effects the engagement of the worm a' is fixed upon the
shaft d' which latter receives its motion from the worm d in the manner described.
The screwing forward of the screw cutter E' which is placed on the front end of
the hollow shaft is effected by the gearing E comprising the belt pulleys e and e
revolving in opposite directions, and the toothed wheels, which latter engage
spur wheels upon the shafte. The pulleye and the toothed genring e*e* whose
relative speeds are somewhat in the proportion of 3 to 4 and which consequently
when they are in operation, cause a somewhat slower revolution of the hollow shaft,
effect the serewing forward of the latter whereas the pulley with the toothed
gear whose relative speeds are approximately as two to one, consequently cause
a quicker revolution of the hollow shaft and effect the quick screwing back of the
tool when the screw thread has been cut. The connection of this mechanism that
is the coupling of either of the toothed wheels with the shaft is effected
through the clutch muffs ee' by means of double arm adjusting levers whose upper
arms surround these muffs in the form of forks in such manner that each adjusting
lever alternatively brings its muff in contact with the corresponding toothed wheel
and thereby couples the latter firmly with the shaft. To the muff which clutches
the tooth wheel and thereby connects the gearing and e³ in order to screw the
tool forwards, there belongs the adjusting lever at whose lower arm a
horizontally placed bar is joined. This piece is under spring pressure and rests
with its free end against a suitably constructed disc f' which has a recess into
which the end of the bar f can slip and which is fixed upon a cross shaft driven
from the shaft c. This connection results in the movement of the muff and
consequently the coupling of the shaft with the genring ee. The hollow shaft
will consequently revolve slowly, whereby a screwed sleeve & fastened upon the
same and which gears with a female screw in a piece will cause an end wise

page_text: forward motion of said shaft. This piece which may be divided into parts
having female screw threads of different pitch is revolubly mounted on a support
in such a manner that it may be rotated to bring either of its divisions into action
and thus various kinds of screws can be cut according to requirements; various
screwed sleeves must however be at hand for interchanging. To the muffe
which clutches the geared for the quick return, there belongs the adjusting
lever to whose lower arm ell a bar is connected acting similarly to the
bar upon the adjusting lever (see Figure 2).
The hinder end of this bar is divided and there is placed between the two
parts which are provided with teeth (Figure 7), a little spur wheel" in such
a manner that a so-called reversing mechanism is formed. The separated part f*
rests against a disc corresponding to one of the disc f and mounted upon the
same shaft, against which disc it is pressed by means of a spiral spring acting upon
the bar. This disc f' has again a notch in the same way as the disc f¹ in which
the part can engage, whereby in consequence of the reversing mechanism, the
bar moves in the opposite direction and the adjusting lever ee" will turn so
that the muffe clutches the toothed wheel e' upon the shaft eo, and thereby causes
the connection of the gearing eee which effects the screwing back of the toul.
The gripping of the work is effected by means of the chuck K which is screwed
into the hollow spindle which is correspondingly widened at its front end, said
chuck having in its interior conical cheeks k which are pressed by means of the
sleeve against the corresponding conical inner surface of the chuck and thereby
the work is held firm.
The material to be turned down and screwed is placed inside the sleeve and
can be pushed forward by means of the feeder 7 acting upon its hinder end under
the influence of a counterweight as soon as the cheeks are opened. The opening
of the cheeks and the pushing forward of the work is naturally effected when the
parting tool has effected its work and a newly turned piece of material has to be
brought within the reach of the tools. In order to open the checks the same must
be drawn away from the conical interior of the chuck, and consequently must be
drawn back by the sleeve k. This alteration of the sleeve is effected by means
of a muff arranged adjustably upon the spindle and two diametrically opposite
placed lever connections, one member of which is attached to the muff k³,
whilst the other member, the elbow lever is connected with its longest arm to
the lever and holds with its other arm to a projection on the end of the
sleeve. This elbow lever is attached to suitable projections of a ring screwed
upon the spindle ko. It is obvious that when the muff 3 is pushed to the left, the
lever turns to the left and hereby the elbow lever draws the sleeve k¹ to
the left whereby the cheeks are loosened in the chuck. The apparatus for
the adjustment of the muff is a lever m grasping the same with its upper end in fork
shape, and it divides below into two arms of which the one bears the roller m
working upon the disc m³ and the other the roller m³ working upon the disc m
Both discs are placed upon a shaft mo which receives its motion from the
gearing d d from the shaft d'; one of the discs m³ has a piece cut out m³, whilst
the other m has a projection. These dises actuate alternately the lever mand
impart to the same according to the position of the cut out piece and of the pro-
jection at a given time a push to the left or to the right, and thereby effect the
displacement of the muff and the adjustment of the cheeks. As soon as the
cheeks k are open, the advance of the work follows automatically for the stopping
of which a further special arrangement is provided. This arrangement consists of
a bar adjustably placed in the hollow shaft and which possesses at its front end
a stop . This stop limits the advance of the work at a given time because as soon
as the latter has advanced the length of a screw out of the cheeks it encounters
said stop and further advance of the work is thus prevented until the cheeks have
closed, that is until the sleeve k¹ which moves forward is pressed into the cone of
the chuck thereby locking the cheeks. The forward movement of the bar is
effected by means of a double arm lever whose upper end embraces in fork shape

page_text: a muff on the bar l, and whose lower end is provided with a roller pressing upon
a cam disc which gives the lever the necessary movement to adjust the bar ...
The lever 13 is pressed on the cam disc by means of a spiral spring which is fixed
to the frame and attached to a cross arm of the lever. The disc is fixed upon
the cross shaft bearing discs f¹ which as already stated receives its motion from
the shaft e by means of a bevel gearing (see Figure 3). Upon the spindle ko sits
loosely the cone pulley M which can effect the turning of the spindle by means of
the adjustable coupling disc N. Whilst screw cutting. the work must of course be
held fast, therefore the connection between the disc N and the stepped pulley M
must be released and the spindle held fast. For this purpose there is fixed upon
the hub of the disc N another conical disc N' which when the first has disengaged
from the stepped pulley enters into a fixed disc N2 supported by the frame of the
machine, whereby the spindle is coupled with this immovable disc and consequently
is held fast. An adjusting lever n serves to move the disc N in and out, which
lever is pivoted to the frame and holds with its upper arm the hub of the disc N
whilst the lower end rests with a roller against the cam discs n' n² whose projections
actuate the lever arm and thus effect the movement of the levers (Figure 6)..
These cam dises n¹ n² are adjustable with relation to one another, consequently the
total projection or cam surface working upon the lever arm relative to the extent.
of their periphery can be varied according to requirements.
This improved screw making machine does not contain a device for cutting the
slot in the screw, but any suitable device for this purpose may be affixed to the
machine if desired.
The process of working of the machine is as follows:-
1. Opening of the cheeks, advance of the work, simultaneous advance of the stop,
closing of the cheeks, return of the stop.
2. The support table A' with the shaping tool is pushed against the work so that
the tool can act, the support is moved to the left, shaping of the screw, at the end
of the motion of the support the tool holder A2 descends, the preliminary cutting
or grooving tool comes into play, the screw is grooved or partly cut off above the
head to the depth of the shank.
3. Shaping and grooving finished, table A' is drawn back with the tools from
the work, support A moves to the right, screw cutter E is screwed forward and the
thread cut, stepped pulley M is disconnected and the guide spindle with adjusting
head is fixed.
4. Screw thread cutting finished, screw thread cutter is drawn back, supporting
table B' with parting tool is pushed forward, the screw is parted at the grooved
part, the finished screw falls out of the machine.
5. Opening of the cheeks etc.
I, WILLIAM PHILLIPS THOMPSON, F.C.S., M.I.M.E., of The Agency for
Foreign Patent Solicitors 322 High Holborn in the County of Middlesex 6 Lord
Street, Liverpool, and 6 Bank Street, Manchester, both in the County of
Lancaster, and Lower Temple Street, Birmingham in the County of Warwick,

page_text: Civil Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and
by the following statement :-
The present invention has for its object an automatic screw cutting machine, in
which the advance of the work, the support of the shaping tools and the backwards
and forwards motion of the support table with the tools as well as the backwards
and forwards motion of the screw cutting mechanism is effected completely
automatically by means of suitably arranged mechanisms in combination with
reversing gearing. Moreover there are provided in the machine adjusting
mechanisms working entirely independently of one another for the shaping, the
cutting out of the screw, the screw thread cutting and the moving of the work,
which motions are controlled by the employment of adjustable wheel gearing and
adjustable cams or discs in order to make the length of the course of the working
organs always correspond to the measurements of the kind of screw then to be
made. In this machine moreover the driving mechanisms for the lathe and for the
screw cutting tool are arranged to work separately from one another and inter-
changeably in order to render possible the insertion of wheels for the purpose of
altering the speed, in such manner that in the machine together with the length of
the stroke, the speed also of the working orgaus can be altered corresponding to
the size and strength of the screws.
In the drawings illustrating the invention, accompanying the Provisional
Specification, by way of example-
Figure 1 is a front view partly in section of the machine;
Figure 2 is a back view of the same;
Figure 3 is an end elevation viewed from the right;
Figure 4 is a vertical cross section on the line -x of Figure 1;
Figure 5 is a vertical cross section on the line y-y of the same figure;
Figure 6 is an end elevation viewed from the left, the advancing mechanism for
the work being left out;
Figure 7 is a detail.
A is the support carrying the shaping tools which as previously indicated
receives its horizontal motion parallel with the work from the common driving gear
of the reversing mechanism (namely the stepped cone a upon the shaft aº) by
means of suitable intermediate mechanism. Upon the shaft a° are placed two
loose worns of which the one a' as soon as the support is to be pushed to the left
for the purpose of shaping the work, comes in gear with the coupling muff g keyed
adjustably upon the shaft, in such manner that it revolves with the latter and so
shares the rotation of the shaft aº.
The worm a acts upon a gear wheel a² and from this the motion is transferred
through gearing a³ as a as to the eccentric a' fixed upon the cross shaft aⓇ which
forms the actuating organ for the adjustment of the support when the screw is
being shaped.
The periphery of this eccentric is formed in the shape of a snail-cam having a
sharp heel surface which is directed radially, and forms the descent from the
highest point of the eccentric to the lowest point. The support frame A has on
one side a projecting piece a resting upon the surface of the eccentric a' and is
pressed with the latter firmly against the eccentric by the pressure of a spring.
By altering the adjustment of the parts a³ and a7 or changing the part a the
movement of the support may be varied to correspond to the length of the screw.
When the support has arrived at its furthest position to the left, and consequently
the shaping of the work is just finished, the beel surface of the eccentric will have
come under the projection of the support. The projection has then passed the
.highest point of the eccentric, and the support will in the next moment under the
pressure of the spring fly back into its original position to the right. This moment
(that is the position of the parts at this moment) is shown in the drawing. Beside
the support A a two armed tool holder A2 is pivotally attached to a piece a¹º

page_text: arranged upon the cheeks of the bed, the upper arm of which tool holder carries
a cutting tool. The lower arm of this tool holder is provided with a roller all
which lies upon a shaped piece a secured upon the supporting tahle A'. When
the support moves to the left, the roller a" on this shaping piece a slides upwards,
the bead of the holder carrying the tool will sink, and the tool will groove or
partly cut off the work in the proper manner on the top of the screw head to the
same depth as the shaper has cut the screw shank on the other side of the head.
The position of the roller upon the highest point of the forming piece corresponds
to the left position of the support shown in the drawing. The work is thus partly
cut off, and with the springing back of the support, into its right side commencing
position the roller of the pivoted tool holder, will roll down the surface of the
forming piece, and the other arm of the tool holder correspondingly rise so that
the tool is drawn away from the work, the partly formed screw being still connected
to the work by a neck having the diameter of the screw shank. The bringing
forward of the supporting table A' with the shaping tools to the work into the
working position, that is the shifting of the table 'A' at a right angle to the motion
of the whole support is effected by means of a two armed lever 667 which is hung
between the cheeks of the support and has a toothed segment on its upper arm
which engages in a corresponding rack on the lower surface of the adjustable table.
The lever lies with its lower arm & against the edge of a dise fixed upon.
the shaft 3, and which has a recess 6. Into this recess the arm slips as soon
as the shaping tool has finished its cut, that is when the support A is in the position
shown in the drawing as clearly shown in Figure 5. In this figure, corresponding
to the position of the other parts, the disc 63 is in such a position that at the next
moment the arm will slip into the recess whereupon a spiral spring fixed in
the supporting table can spring the latter back, the recess in the disc allowing the
lever so much play that it can make the corresponding movement.
The shaping tool will consequently be drawn away from the work until the
recess has passed the lever arm 66, whereupon in consequence of the arm again
slipping over the full surface of the eccentric the lever makes the opposite motion,
whereby its upper end again advances the supporting table. The shaft bearing
the disc 63 is driven by means of. bevel wheel gearing from the shaft a³
(see Figure 4).
The disc is of course adjustably fixed upon the shaft 2 so that it can be carried
along by the support A in its movement to and fro. The movable support. A has
opposite to it a fixed support B which carries the parting tool, the table B' of
which support B is movable in a similar manner to the table A' of the support A
at a right angle to the work. In order to effect this displacement there is provided
a double lever c² 3 which is actuated by means of a tappet c' fixed upon the shaft c
and behind which the lower arm c2 engages, whilst the upper arm c³ has a toothe
segment which works in a corresponding rack on the under surface of the table B.
In Figure 5 the lever ee and the tappet e stand in such a position that in the
next moment the latter will give to the former a motion causing the advance of the
table. The table is also provided with a spring which throws it back again into
the position -hown in Figure 5 as soon as the parting is accomplished and the
tappet el has passed the lever c.
The shaft c receives its motion from the worm d by means of gearing d' d
d' d' d' d' d' as soon as the coupling muff g fixed upon the shaft a has been
moved to the left, out of the position shown in the drawing, and the end thereof
has been brought into gear with the clutch disc attached to the worm d whereby
the worm a¹ is disconnected and d connected.
It is moreover obvious that this discounection of the worm a¹ and the connecting
of the worm d can only then take place after the screw has been shaped and the
parting tool as well as other mechanisms to be hereinafter described which disengage
the apparatus for the turning of the head and effect the movement of the work and
limit it, have been set in motion. The displacement of the coupling muff g is
effected by means of connection gunder spring pressure with whose lower arm y

page_text: a fork surrounding the muff is connected. The moving of this connection to the
right or to the left is effected by means of a guide rod 9 which engages in a slot of
the lever and which has two notches o7 98, placed each close to one end of it
respectively, in which the claws of two discs 910 can engage. As soon as the
-disc go upon the shaft a has pushed the bar to the right in the manner shown in the
drawing, the connection, whose upper bar y is mounted in a guide pivotally attached
to the frame, will strike out in the same direction whereby the muff g is pushed
to the left by the fork g' and the coupling of the worm d with the shaft a° is
effected.
When the working process is ended, that is when the screw is cut, the finished
screw is cut off or discharged and the work is again pushed forward; the disc g
then comes into action which engaging with its finger in the notch g' pushes the
bar g to the left, in consequence of which the connection g g strikes to the left
whereby the muff g is pushed to the right and the worm a' is again so connected with
the shaft a that the shaping can take place. As already stated, the disc 9" which
causes the engagement of the worm d is fixed upon the shaft a which consequently
receives its notion from the worm a' through the intermediate gear a² to a'. The
disc which effects the engagement of the worm a is fixed upou the shaft d
which latter receives its motion from the worm d in the manner described.
The screwing forward of the screw cutter E which is placed on the front end of
the hollow shaft is effected by the gearing E comprising the belt pulleys e and e¹
revolving in opposite directions, and the toothed wheels which latter engage
spur wheels upon the shaft . The pulley e and the toothed gearing ee
whose relative speeds are somewhat in the proportion of 3 to 4 and which
consequently when they are in operation, causes a somewhat slower revolution of
the bollow shaft, effect the screwing forward of the latter, whereas the pulley e
with the toothed gear ee whose relative speeds are approximately as two to one,
consequently cause a quicker revolution of the hollow shaft and effect the quick
screwing back of the tool when the screw thread has been cut. The connection of
this mechanism that is the coupling of either of the toothed wheels ee with the.
shaft is effected through the clutch muffs ee by means of double arm adjusting
levers whose upper arms sur round these muffs in the form of forks in such manner
that each adjusting lever alternatively brings its muff in contact with the
corresponding toothed wheel and thereby couples the latter firmly with the shaft.
To the muff which clutches the tooth wheel and thereby connects the
gearing 3 and 2 in order to screw the tool forwards, there belongs the adjusting
lever at whose lower arm a horizontally placed barf is joined. This piece is
under spring pressure and rests with its free end against a suitable constructed
disc which has a recess into which the end of the bar can slip and which is
fixed upon a cross shaft driven from the shaft c. Said disc consists of two parts
adjustable on one another so that the length of the recess may be adjusted to suit
long or short threads. This connection results in the movement of the muffe and
consequently the coupling of the shaft with the gearing e e³. The hollow shaft
will consequently revolve slowly, whereby a screwed sleeve h fastened upon the
same and which gears with a female screw in a piece will cause an endwise
forward motion of said shaft. This piece which may be divided into parts
having female screw threads of different pitch is revolubly mounted on a support.
in such a manner that it may be rotated to bring either of its divisions into action
and thus various kinds of screws can be cut according to requirements; various
screwed sleeves h must however be at hand for interchanging. To the muff '
which clutches the gear for the quick return, there belongs the adjusting
lever to whose lower arm ell a bar is connected acting similarly to the
bar upon the adjusting lever ese (see Figure 2).
The hinder end of this bar is divided and there is placed between the two
parts which are provided with teeth (Figure 7), a little spur wheel in
such a manner that a so-called reversing mechanism is formed. The separated
rests against a disc f corresponding to one of the discs f' and mounted
part

page_text: upon the same shaft, against which disc it is pressed by means of a spiral spring
acting upon the bar f. This discy has again a notch in the same way as the
disc in which the part f' can engage, whereby in consequence of the reversing
mechanism the bar fmoves in the opposite direction and the adjusting levere e
will turn so that the muff e' clutches the toothed wheel upon the shaft e°, and
thereby causes the connection of the gearing eel which effects the screwing
back of the tool. The gripping of the work is effected by means of the chuck K
which is serewed into the hollow spindle 4 which is correspondingly widened at its
front end, said chuck having in its interior conical cheeks k which are pressed by
means of the sleeve against the corresponding conical inner surface of the chuck
and thereby the work is held firm.
The material to be turned down and screwed is placed inside the sleeve ¹ and
can be pushed forward by means of the feeder & acting upon its hinder end under
the influence of a counterweight as soon as the cheeks are opened. The opening
of the cheeks and the pushing forward of the work is naturally effected when the
parting tool has efferted its work and a newly turned piece of material has to be
brought within the reach of the tools. In order to open the checks the same must
be drawn away from the conical interior of the chuck, and consequently must be
drawn back by the sleeve k'. This alteration of the sleeve is effected by means
of a muff arranged adjustably upon the spindle and two diametrically opposite
placed lever connections kk, one member of which is attached to the muff k³,
whilst the other member, the elbow lever is connected with its longest arm to
the lever and helds with its other arm to a projection 2 on the end of
the sleeve . This elbow lever is attached to suitable projections of a ring
screwed upon the spindle . It is obvious that when the muff is pushed
to the left, the lever turns to the left and hereby the elbow lever draws
the sleeve to the left whereby the cheeks are loosened in the chuck.
The apparatus for the adjustmeat of the muff is a lever m grasping the
same with its upper end in fork shape, and it divides below into two arms of
which the one bears the roller m' working upon the disc m³ and the other the
roller m working upon the disc m. Both dises are placed upon a shaft m which
receives its motion from the gearing d do from the shaft d'; one of the discs m³
has a piece cut out m, whilst the other m has a projection. These discs netuate
alternately the lever m and impart to the same according to the position of the cut
out piece and of the projection at a given time a push to the left or to the right,
and thereby effect the displacement of the muff and the adjustment of the cheeks.
As soon as the cheeks k are open the advance of the work follows automatically,
for the stopping of which a further special arrangement is provided. This
arrangement consists of a bar I adjustably placed in the hollow shaft and which
possesses at its front end a stop . This step limits the advance of the work at a
given time because as soon as the latter has advanced the length of a screw out of
the cheeks, it encounters said stop and further advance of the work is thus
prevented until the cheeks have closed, that is until the sleeve which
moves forward is pressed into the cone of the chuck, thereby locking the cheeks.
The forward movement of the bar is effected by means of a double arm lever 13
whose upper end embraces in fork shape a muff on the bar l, and whose lower
end is provided with a roller pressing upon a cam dise which gives the lever P
the necessary movement to adjust the bar . The lever 13 is pressed on the cam
disc by means of a spiral spring which is fixed to the frame and attached to a
cross arm of the lever. The dise is fixed upon the cross shaft bearing discs f
which as already stated receives its motion from the shaft c by means of a bevel
gearing (see Figure 3). Upon the spindle sits loosely the cone pulley M
which can effect the turning of the spindle by means of the adjustable coupling
disc N. Whilst screw cutting, the work must of course be held fast, therefore the
connection between the disc N and the stepped pulley M must be released and the
spindle held fast. For this purpose there is fixed upon the hub of the dise N
another conical disc N which when the first has disengaged from the stepped
B

page_text: pulley enters into a fixed disc N2 supported by the frame of the machine whereby
the spindle is coupled with this immovable disc and consequently is held fast. An
adjusting lever n serves to move the disc N in and out, which lever is pivoted to
the frame and holds with its upper arm the hub of the disc N whilst the lower end
rests with a roller against the cam discs n' n whose projections actuate the lever
arm and thus effect the movement of the disc N (Figure 6). These cam discs n' n
are adjustable with relation to one another, consequently the total projection or
cam surface working upon the lever arm relative to the extent of their periphery
can be varied according to requirements.
This improved screw making machine does not contain a device for cutting the
slot in the screw, but any suitable device for this purpose may be affixed to the
machine if desired.
The process of working of the machine is as follows:-
1. Opening of the cheeks, advance of the work, simultaneous advance of the
stop, closing of the cheeks, return of the stop.
2. The support table A' with the shaping tool is pushed against the work so that
the tool can act, the support is moved to the left, shaping of the screw, at the end
of the motion of the support the tool holder A2 desceuds, the preliminary
cutting or grooving tool comes into play, the screw is grooved or partly cut off
above the head to the depth of the shank.
3. Shaping and grooving finished, table A' is drawn back with the tools from
the work, support A moves to the right, screw cutter E is screwed forward
and the thread cut, stepped pulley M is disconnected and the guide spindle with
adjusting head is fixed.
4. Screw thread cutting finished, screw thread cutter is drawn back, supporting
table B with parting tool is pushed forward, the screw is parted at the grooved
part, the finished screw falls out of the machine.
5. Opening of the cheeks, etcetera.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondents, I declare that what I claim is :-
1. An automatic screw cutting machine in which the opening and closing of the
cheeks (k), the movement of the stop () for limiting the pushing forward of
the work piece, the movement of the shaping tools and of the supports (AA) and
supporting table (A' B'), and reversal of the gearing, are automatically effected by
means of suitable gearing and mechanism, characterised by adjusting mechanisins
working independently of one another for the shaping, the moving of the work,
and the operating of the screw thread cutting, the motions of which mechanisms
by the use of interchangeable gearing and adjustable eams are rendered capable of
being altered, in order to allow of the adjustment being always regulated to
correspond to the measurements of the screw to be made, whilst the driving
mechanisms for the lathe and for the screw thread cutting tool are arranged to work
separately from one another and interchangeably in order to render possible the
insertion of change wheels for the purpose of altering the speed in such inauner
that in the machine together with the length of the stroke, the speed also of the
working organs can be altered corresponding to the size and strength of the screws,
substantially as herein before described and illustrated.
2. In an automatic screw cutting machine of the kind described, the device for
alternately operating on the one hand the gearing for the shaping and on the other
hand, the screw thread cutting, parting of the screw, and moving of the work, or
rather their reversing mechanisms, consisting of two clutch couplings (9 g and g g²)
suitably connected with worms (a' and d) which serve as driving organs, the
cominon muff (9) of said clutch couplings being operated at a given moment by
the for the time being actually working but about to be disconnected gearing, by
means of a fork connection (93 gy) operated by a guide rod (9) in such a way
that the fixing of the one worm and the releasing of the other worm on the driving

page_text: shaft is effected simultaneously, the gearing which has finished its work being
thereby disconnected, and the gearing for undertaking the further treatment being
thereby connected, substantially as described.
3. In an automatic screw cutting machine of the kind described, the arrangement
for alternately connecting and disconnecting the stepped pulley (M) on the-
spindle (°) of the chuck (K) for the purpose of disengaging this pulley and
stopping the spindle during the screw thread cutting, and for fixing the pulley on
the spindle and freeing the latter during the shaping, characterised by an adjusting
lever (n) and suitable cam discs (n' n³) for operating the respective couplings (N' N
and N M), said cam discs which come into action as soon as the shaping of the
screw is ended and cause the adjusting lever to operate the respective couplings are
mutually adjustable in order to render the releasing of the pulley and stopping of
the spindle of longer or shorter duration corresponding to the duration of the
screw thread cutting according to the dimensions of the thread, substantially as
described.
4. In an automatic screw cutting machine of the kind described, the device for
moving forward and backward the screw thread cutting tool, characterised by
adjusting levers (e8e and elo ell) for effecting the varying engagement of the
respective gearings and their coupling clutch muffs, the actuating bars (f and f).
of which adjusting levers are operated by discs (f¹ and f) provided with recesses,
which discs each consist of two parts adjustable on one another in order to allow of
the length of the respective recesses being regulated and of the movement being
thereby set for long or short threads, fixed screw pieces (h) being also provided to
restrict the movement of the cutter substantially as described.
5. In an automatic screw cutting machine of the kind described, the arrangement
for adjusting the horizontally movable support (A) for carrying the shaping tools,
by means of a cam (a) acting against a contact piece (a), in such a way that by
altering the adjustment of both or changing the latter, the movement of the
support may be varied corresponding to the length of the screw, substantially
as described.
6. In an automatic screw cutting machine of the kind described, the arrangement
for moving the tool holder (A2) carrying the preliminary cutting or grooving tool,
consisting in the holder being formed as a two armed lever pivotally mounted on a
support (a), its lower arm being provided with a roller and adapted during the
moving into action of the support (A) to slide upwards on a shaped piece (a).
having an inclined running surface fixed upon the table (A') for the shaping tool,
in such a way that by changing this shaped piece the depth to which the tool cuts
may be suitably varied to the thickness of the screw, substantially as described.
7. The general construction and combination of parts taken as a whole, forming
the improved screw cutting machine substantially as herein before described and
illustrated.
WM. P. THOMPSON & Co.,
Agents.