Year: 1888

page_text: I, MARTIN BISCHOFF, of Schwelm, Westphalia, in the Empire of Germany, Lock-
smith do hereby declare the nature of this invention to be as follows:-
This invention relates to a machine for automatically cutting the threads on screw
bolts, the heads of which are of square or hexagonal shape, or round, and provided
with a groove or saw cut for the screw driver.
The machines heretofore used for this purpose do not operate automatically, but
require the continual aid of a workman, whereas the machine constructed according
to the present invention requires a workman only, when, through any accident,
the operation is interrupted or when the machine must be supplied with fresh
material.
In the machine constructed according to my invention the screw cutter and the
griper, feeder, hand and pan are formed as in the known machines, but the arrangement
for engaging with the groove or saw-cut or taking hold of the hexagonal or square
head, and also the remaining mechanism of the machine is new.
On the frame are supported the upper and lower shafts the latter of which serves
as the driving shaft and is provided with a pulley.
The upper shaft does not turn directly in its bearings but turns with a socket or
sleeve which surrounds it and in which it can be displaced longitudinally. This
socket is driven by the lower or driving shaft through the medium of the toothed
wheels and the toothed couplings belonging to these wheels. Upon the said socket
is arranged a double-sided toothed coupling for the toothed wheels on the socket and
upon the driving shaft a simple coupling for the pinion on the said shaft and the cor-
responding wheel on the upper shaft.
The upper shaft possesses at one end a slightly taper grooved disc and at the other end
a chuck for receiving a screw-driver as in the present case or of a holder with a square

page_text: or hexagonal depression according as the screws are formed with a grooved or with
square or hexagonal heads. The chuck is enlarged at the rear end to form a disc
upon the back side of which move a pair of rollers which effect the displacement of
the upper shaft. In the prolonged axis of the upper shaft is the screw plate formed
as in the known screw-cutting machines and fixed in the screw plate holder. The
latter can be adjustably secured upon the frame according to the length of the
screws.
Upon the frame is also supported a cam shaft which carries eight cam discs of
suitable shape.
The double claw coupling of the socket or sleeve is operated from the first cam
dise by means of the disengaging lever. The second cam disc regulates the io-and-fro
motion of a square rod which by a suitably arranged spring presses the roller fork
fixed upon it against the chuck which pressure is then transmitted to the screw
driver.
The third cam disc upon the cam shaft causes the engagement of the claw coupling
of the driving shaft by means of a second disengaging lever when the screw to be
cut is to be inserted and brought before the screw plate.
The fourth cam dise effects the motion of a short auxiliary shaft, which carries the
lever. The latter is designed to set the inserted slide of the screw plate holder in
motion. A lever is actuated at the same time by this slide through the medium of
a connecting piece; both firmly hold the griper at the time of the insertion with the
screw to be cut upon the middle until the screw driver has entered the groove. With
long screws the holding of the griper is effected by a second pair of lovers; in this
case the inserted slide and the first mentioned lever. holds the shaft of the screw upon
the middle of the screw plate. The fifth cam disc moves the short shaft by means
of the lever which carries griper levers fixed thercon for taking hold of and inserting
the screw to be cut; the griper is enclosed by two springs, one of which keeps it
in the direction, and the other holds it together with the screw.
The sixth cam dise acts upon a lever which is placed upon the auxiliary shaft and
whereby a lever device and mechanism is set in motion, which actuate in a known
manner a fork fixed to the feeder, and a hand so that the screws to be cut are con-
ducted to the griper. In like manner, as already known, a pan or plate for the
reception of the screws to be cut is set in motion by the cam shaft.
The seventh cam disc acts by means of levers upon a pin which retains the chuck
according to requirements.
By a lever on the cam shaft the spring pressure upon the square rod is to
be partially removed at the time when the screw driver is inserted in the screw
head.
The cam shaft is actuated by the driving shaft by means of change wheels the
size of which depends on the length of the thread on the screw to be cut. The
wheels are such that the cam shaft has to make a complete revolution for every cut
screw.
Upon the frame is also supported a shaft, a lever upon which shaft, operates upon
the grooved disc of the upper shaft. On the said lever dropping into one of the
grooves of the grooved disc a slide is moved by means of a lever and acts upon a
pin of the disengaging lever of the double coupling so that the coupling is dis-
engaged. The auxiliary shaft is connected with the square rod by a connecting
piece which is fixed upon the said auxiliary shaft but does not prevent a displace-
ment of the said square rod. The aforesaid piece has for its object to impart at times
a stronger pressure to the roller fork by means of spring traction when the thread is
cut, inasmuch as the connecting piece presses against an adjusting ring secured upon
the square rod.
On setting the machine in motion the aforesaid well-known mechanism consisting of
a fork pan, feeder and hand will begin to operate in such a manner that the fork by
the action of the lever mechanism which is set in motion by a lever placed upon the
auxiliary shaft, receives one or more of the screws to be cut which rest on the pan,

page_text: and conveys them to the feeder which then allows them to pass to the hand. The
griper fixed to the griper lever when the hand with the screw to be cut arrives, will
then descend a little by a jerk, take hold of the screw and firmly seize it by a spring,
whereupon the hand passes back to take upon another screw. The jerk motion is pro-
duced by a depression in the fifth cam disc into which a lever strikes.
By this motion the screw is conducted to the middle of the screw plate and firmly
held by the slide and lever. A part of the spring pressure, removed by the first cam
disc upon the upper shaft now comes into action, whereby the screw driver presses
against the head of the screw and presses the latter against the screw plate. The
stronger spring of the pressing piece is held back by the lever on the cam shaft until
the cutting takes place. In this time the claw coupling of the driving shaft has
been brought into engagement by the third cam disc, thereby setting the socket or
sleeve and at the same time the screw driver in the slowest motion by means of the
toothed wheel and pinion on the upper and lower shafts respectively. The double
claw coupling is still out of engagement. By this slow motion the entrance of the
screw driver into the groove of the head is effected. After this has been accomplished
after one turn, the coupling of the driving shaft is again disengaged by the third cam
disc and the double claw coupling of the socket or sleeve is caused by the first cam
disc to engage for the cutting so that other wheels set the upper shaft in rotation.
Meanwhile the lever on the cam shaft has advanced so far that the stronger spring of
the pressing piece can act upon the square rod. The slide and lever now releases the
griper and moves back sufficiently to leave room for the head of the screw, whereupon
the said griper can move upwards in order to fetch during the time of the cutting
another screw to be cut. When the screw has been cut as far as the head, the
grooved dise has advanced so far that in the latter half of the revolution one of the
grooves passes above the lever, whereby the latter is compelled by means of spring
pressure to pass deeper and deeper into the same; another lever on the same shaft is
thereby moved and the slide operates with an inclined side upon the disengaging
lever of the double claw coupling and puts it out. The first cam disc will then con-
duct the coupling to the opposite toothed pinion and thereby set the socket or sleeve
on the upper shaft in rapid rotation in the opposite direction, and thus cause the cut
screw to he turned out. In the back motion the grooved disc will depress the
lever again, the latter bears again upon the circumference of the disc; and the slide
returns to its original position. During the turning of the cut screw from the screw
plate the pressure of the roller fork upon the upper shaft is relieved by the second
cam disc. In order that in the rapid turning of the cut screw from the screw plate
the screw driver shall remain in the groove the grooved disc is made taper,
whereby the pressure upon the lever also comes in action in axial direction. When
the screw is entirely turned out, the square rod is drawn still further back by a
steeper projection of the second cam disc whereby a carrier lever fixed to the roller
fork draws the upper shaft still further back to provide room for a fresh screw to be
cut; at the same time the double claw coupling discontinues its action, and the
griper can now feed a fresh screw.
Should the case occur that no screw is fed, and that therefore the pressure of the
square rod does not act upon a screw to be cut, two rapid an advance of the upper
shaft against the griper would take place. In order, therefore, to prevent contact the
lever upon the seventh cam disc raises a pin which strikes in front of the chuck of
the upper shaft and remain there until the griper has passed hack. In the further
rotation the second can disc permits a further advance of the upper shaft until
the lever passes into a groove of the grooved disc and sets the claw coupling at
rest.
In order that in the rapid turning of the cut screw from the screw plate the screw
shall not stop in the last thread of the said plate, on the back side of the screw plate
holder is arranged a
casing in which is guided a pin that extends into the screw
plate and is flush therewith. By two springs this pin is compelled to follow the
motions of the screw, whereby a stoppage in the last thread is obviated in the
turning motion for removing the same.

page_text: In like manner, in order to effect the dropping from the screw driver, upon the boss
of the chuck is arranged a spring which presses against the head of the screw to
throw the latter out when it is liberated. The levers working upon the cam discs are
compelled by springs to carry out the motions in their closed positions.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.
Improvements in Machines for Cutting Screw Threads on Bolts and
the like.
I, MARTIN BISCHOFF, of Schwelm, Westphalia, in the Empire of Germany,
Locksmith, 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 :-.
This invention relates to machines for automatically cutting the threads on screw
bolts, the heads of which are of square or hexagonal shape, or round and provided
with a groove or saw cut for the screw driver.
The machines heretofore used for this purpose do not operate automatically, but
require the continual aid of a workman, whereas the machine constructed according
to the present invention requires a workman only when through any accident
the operation is interrupted or when the machine must be supplied with fresh
inaterial.
In the machine the screw cutter and the griper N feeder, hand and pan are
formed as in the known machines, but the arrangement for engaging with the
incision or taking hold of the hexagonal or square head, and also the remaining
mechanism of the machine is new.
The improved machine is represented in the accompanying drawings in which,
Figure 1 shows a plan of the machine.
Figure 2 is a side view of the part of the frame on the right-hand side of
Figure 1 showing the disc H actuating the coupling lever P, and the coupling
lever to be moved by the disc H³, moreover the pitch circles for the toothed
driving wheel of the shaft G.
Figure 3 is a section on the lineæ, & Figure -1.

page_text: Figures 4, 4 and 5 show the arrangement of the disengaging device, which is
actuated by the cain C, of the coupling upon the sleeve B.
Figure 6 shows the fork K provided with friction rollers and acting upon the
cam
Figure 7 shows the griper to be operated by the cam H, and the clamping
device of the same to be driven by the cam El³ and arranged nearest the screw-
plate.
Figure 8 shows the clamping device arranged near to the screw driver.
Figure 9 shows the driving of the known feed mechanism by the disc H³.
Figure 10 shows the key J upon which the cam H acts.
Figures 11 and 11ª shows the cams H¹ and H' which displace or retain the
pins on the rod G' and connecting-bar W.
Figure 12 shows a horizontal section through the screw-ejecting device.
On the frame A are supported the upper and lower shafts C and E the latter
of which serves as the driving shaft and is provided with a pulley F Figures 1,
2 and 3.
The upper shaft C does not turn directly in its bearings but turns with a socket
or sleeve B which surrounds it and in which it can be displaced longitudinally.
This socket is driven by the lower or driving shaft E through the medium of the
toothed wheels Z, Z', Ž², Z³ and Z, Z and the toothed couplings belonging to
these wheels. Upon the said socket B is arranged a double-sided toothed coupling
for the toothed wheels Z or Z³ and upon the driving shaft E a simple coupling
for the pinion Z on the said shaft corresponding to the wheel Z' on the upper
shaft.
The upper shaft C possesses at one end a slightly taper grooved disc (and at
the other end a chuck for receiving a screw driver C³ as in the present case or
of a holder with a square or hexagonal depression according as the screws are
formed with a grooved or with square or hexagonal heads. The chuck is enlarged
at the rear end to form a disc (upon the back side of which move a pair of
rollers which effect the displacement of the shaft C. In the prolonged axis of the
shaft C is the screw plate D formed as in the known screw cutting machines and
fixed in the screw plate holder D'. The latter can be secured upon the frame according
to the length of the screws.
Upon the frame A is also supported a cam shaft G which carries eight cam
discs H H1 H2 to H' of suitable shape.
The claw coupling of the socket or sleeve B is operated from the cam disc H by
means of the disengaging lever P which is pressed by a spring R against the cam,
Figures 1 and 2.
The cam disc H' regulates the to-and-fro motion of a square rod G¹ which by a
suitably arranged spring R¹ presses the roller fork K K' fixed upon it against the
chuck which pressure is then transmitted to the screw driver C³ Figures 1, 2,
6 and 11.
The cam disc H upon the cam shaft G causes the engagement of the claw coupling
of the driving shaft E by means of a second disengaging lever Q when the screw to be
cut is to be inserted and brought before the screw plate.
The cam disc H by means of a lever effects the motion of a short auxiliary
shaft G2 which carries the levers L (Figures 1, 7 and 8). The lever L is
designed to set the inserted slide L of the screw plate holder D¹ in motion
Figures 1, 3 and 7.
A lever L² is actuated at the same time by this slide through the inedium of a con-
necting piece, both firmly hold the griper N¹ at the time of the insertion with the
screw to be cut upon the middle until the screw driver C³ has entered the groove.
When cutting long screws the arm N is displaced upon the shaft G3 in such a manner
that the griper N can be seized by the levers L and L Figures 1 and 8; in this
case the inserted slide L' and the first mentioned lever L holds the shank of the screw
upon the middle of the screw plate. The cam disc H' moves the short shaft G³ by means
of the lever 4 which shaft carries the griper lever N, fixed thereon for taking hold of

page_text: and inserting the screw to be cut, Figures 1 and 7, the griper N₁ is enclosed by
two springs and one of which, f, keeps it in the direction, and the other f
holds it together with the screw.
The cam disc H acts upon a lever 5 which is placed upon the auxiliary shaft. G' and
whereby a lever device and mechanism 00' is set in motion, which actuate in a known
manner a fork fixed to the feeder, and a hand so that the screws to be cut are conducted
to the griper. In like manner, as already known, a pan or plate for the reception of
the screws to be cut is set in motion by the cam shaft these parts not being represented
in the drawings.
The cam disc H acts by means of a lever 6 upon a pin J which retains the chuck C²
according to requirements Figures 1 and 10.
By a lever H on the cam shaft G the pressure of the spring R¹ upon the square
rod G¹ is to be partially removed at the time when the screw driver is inserted in the
screw head Figures 1 and 11ª.
The cam shaft G is actuated by the driving shaft E by means of change
wheels I, II, III, IV, V, VI the size of which depends on the length of the thread on
the screw to be cut Figures 1 and 2. The wheels are such that the cam shaft has to
make a complete revolution for every cut screw.
Upon the frame A is also supported a shaft G³, a lever M. upon which shaft operates
upon
the grooved disc C₁ of the shaft C. On the said lever M dropping into one of
the grooves of the grooved disc C¹ a slide V is moved by means of a lever M' and acts
upon a pin of the disengaging lever P of the double coupling so that the coupling is
disengaged, Figures 1, 4 and 5. The auxiliary shaft G is connected with the square
rod G¹ by a connecting piece W which is fixed upon the said auxiliary shaft G* but
does not prevent a displacement of the said square rod Figures 1 and 11, the aforesaid
piece has for its object to impart at times a stronger pressure to the roller fork K by
means of the traction of a spring T Figures 1, 2 and 11 when the thread is cut,
inasmuch as the connecting piece presses against an adjusting ring S secured upon the
square rod Figure 1.
On setting the machine in motion the aforesaid well-known mechanism consisting
of a fork pan feeder and hand will begin to operate in such a manner that the fork,
by the action of the lever mechanism which is set in motion by a lever O, O Figures
and 9 placed upon the auxiliary shaft receives one or more of the screws to be cut
which rest on the pan, and conveys them to the feeder which then allows them to pass
to the hand. The griper N¹ fixed to the griper lever N, when the hand with the screw
to be cut arrives, will then descend a little by a jerk, take hold of the screw and
firmly seize it by a spring, whereupon the hand passes back to take upon another
screw. The jerk motion is produced by a depression in the cam disc H into which a
lever 4 strikes, Figures 1 and 7.
By this motion the screw is conducted to the middle of the screw plate P and firmly
held by the slide L' and lever L, Figure 7. A part of the spring pressure, removed
by the cam disc H upon the shaft C now comes into action, whereby the screw
driver presses against the head of the screw and presses the latter against the
screw-plate. The stronger spring of the pressing piece is held back by the lever H
on the cam shaft G until the cutting takes place. By this time the claw coupling
of the driving shaft has been brought into engagement by the cam disc H² thereby
setting the socket or sleeve B and at the same time the screw driver C3 in the
slowest motion by means of the toothed wheel and pinion on the upper and lower
shafts respectively. The double claw coupling is still out of engagement. By this
slow motion the entrance of the screw driver into the groove of the head is
effected. After this has been accomplished after one complete turn the coupling of
the driving shaft E is again disengaged by the cam disc H² and the double claw
coupling of the socket or sleeve B is caused by the cam disc H to engage for the
cutting so that other wheels and Z3 set the shaft C in rotation. Meanwhile the
lever H on the cam shaft G has advanced so far that the stronger spring T of
the pressing piece W can act upon the square rod G. The slide L' and lever L³ now
releases the griper N¹ and moves back sufficiently to leave room for the head of the

page_text: screw, whereupon the said griper N₁ can move upwards in order to fetch during the
time of the cutting another screw to be cut. When the screw has been cut as
far as the head, the grooved disc has advanced so far that in the latter half of
the revolution one of the grooves passes above the lever M whereby the latter is
compelled by means of spring pressure to pass deeper and deeper into the same;
another lever on the same shaft M' is thereby moved and the slide V operates with an
inclined side upon the disengaging lever P of the double claw coupling and puts it
out. The cam disc H will then conduct the coupling to the opposite toothed pinion Z
and and thereby set the socket or sleeve B or the upper shaft C in rapid rotation
in the opposite direction, and thus cause the cut screw to be turned out. In the
back motion the grooved disc C₁ will depress the lever M again, the latter bears
again upon the circumference of the disc, and the slide V returns to its original
position. During the turning of the cut screw from the screw plate the pressure
of the roller fork K upon the shaft C is relieved by the cam disc H'. In order
that in the rapid turning of the cut screw from the scrow plate the screw driver
shall remain in the groove, the grooved disc is made taper, whereby the pressure
upon the lever M' also comes in action in the axial direction. When the screw is
entirely turned out, the square rod G' is drawn still further back by a steeper projection
of the cam disc H¹ whereby a carrier lever K¹ fixed to the roller fork K draws the
upper shaft C still further back to provide room for a fresh screw to be cut; at
the same time the double claw coupling discontinues its action and the griper N¹
can now feed a fresh screw.
Should the case occur that no screw is fed and that therefore the pressure of the
square rod does not act upon a screw to be cut, too rapid an advance of the shaft (
against the griper N' would take place. In order, therefore, to prevent contact, the
lever 6 upon the cam disc H raises a pin J which would strike in front of the chuck (³
of the upper shaft C and remains there until the griper N¹ has passed back. In the
further rotation the cam disc H₁ permits a further advance of the shaft C until the
lever M passes into a groove of the grooved disc and sets the claw coupling
at rest.
In order that in the rapid turning of the cut screw from the screw plate D the
screw shall not stop in the last thread of the said plate; on the back side of the
screw plate holder D¹ is arranged a casing D³ (Figure 12) in which is guided a pin d
that extends into the screw plate D and is flush therewith Figures 2 and 12. By two
springs d¹ this pin is compelled to follow the motions of the screw, whereby a stoppage
in the last thread is obviated in the turning motion for removing the same.
In like manner, in order to effect the dropping from the screw driver C³, upon the
boss of the chuck C² is arranged a spring (which presses against the head of the
to throw the latter out when it is liberated. The levers working upon
the cam discs are compelled by springs to carry out the motions in their closed
positions.
screw,
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is :-
First. In a machine for cutting threads on screw bolts, the arrangement of a
shaft C with a chuck 02 for the screw-driver C³ or corresponding holders for square
or hexagonal screw heads, the said shaft C turning with the socket or sleeve B
enclosing it, but permitting a displacement in the same and enabling, through the
medium of pressing shaft upon the lever K of the rod G and the cam discs H¹, H',
according to the progress of the work, the groove or the head of the screw which is
to be cut to be automatically seized and released.
Second. The arrangement of a shaft G with the cam discs H2 H' and a toothed
coupling for stopping and applying again the shaft C, and also the driving of
this shaft by means of change-wheels according to the length of the thread to
be cut.

page_text: Third. The arrangement of a double disengaging toothed coupling upon the socket
or sleeve B and the cam disc H actuating the coupling, whereby the corresponding
forward and backward turning movement of the shaft Care effected.
Fourth. The arrangement of a cam C, at the end of the shaft C, so that by the
dropping of the lever M into one of the two grooves of this cam disc a slide V
acts upon a pin of the disengaging coupling and disengages the latter earlier and
more definitely than can be done by the cam disc H alone.
Fifth. The arrangements of levers L' L' Figure 7 with the use of levers L³ L* Figure 8
for longer screws-bolts, and also the motion of these levers against each other by the
cam H so that the gripers N' holding the screw bolt to be cut are so held by the
engagement of the pointed ends of the levers with corresponding depressions that the
screw bolt lies exactly in the axis of the shaft C and screw plate."
Sixth. The arrangements of the wheels Z Z with a disengaging coupling for the
slow turning of the shaft for the purpose of the sure seizing of the groove of the
screw head by the screw driver (³.
Dated this 7th day of December 1888.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London,
Agents for the Applicant.