Improvements in or relating to Turning Lathes and similar Tools.
Year: 1892

page_text: Date of Application, 1st Mar., 1892
Complete Specification Left. 1st Dec., 1892-Accepted, 1st Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in or relating to Turning Lathes and similar Tools.
I, WILHELM VON PITTLER of Maschinenfabrik Gohlis-Leipzig in the Empire
of Germany, Engineer, do hereby declare the nature of this invention to be as
follows:-
This invention relates to improvements in machines of the class set forth in
British Patent No. 8374 of May 25th 1889, though some of the settings or adjust-
ments, are intended for work entirely different from that specified in the said
Patent, the means of operation being, however, much the same, as will be seen.
The arrangement by means of which two screw-threads of different pitch may be
cut without any exchange of wheels, consists in mounting a worm-wheel on each
end of the change-spindle, one of which wheels has a greater number of teeth than
the other.
"
In this machine, the casing with the change-spindle is made capable of revolving
upon the leading screw, and the worm wheels are fixed upon the change-spindle at
the distance from the centre of rotation, so that by turning the case in one or the
other direction, one or the other of the wheels is thrown into gear with the worm...
When the smaller worm wheel is in gear with the worm, the change spindle through
the medium of the change-wheels transmits a greater number of revolutions to the
leading screw-spindle, than when the large worm wheel is in gear with the worm.
In the former case the longitudinally sliding carriage is, in consequence, moved.
more rapidly, and the pitch is increased.
The operation takes place by means of a cord-pulley from which motion is
transmitted to the spindle to which it is rigidly attached and conveyed to the
guiding-spindle by means of a worm, a worm-wheel and the change-wheels.
For cutting spiral grooves, cutters, rimers, worm-wheels, etc., the arrangement
consists of a division-plate rigidly attached to the change-spindle and of a lever
with index securely connected with the worm loose upon the spindle which worm
gears with a worm-wheel mounted upon the spindle.
The lever by means of the index may be set to any desired point of the circum-
ference of the division-plate.
When it is desired to employ the worm-wheel and the worm arranged in the
manner just described, in combination with the change-wheels, not only for cutting
but also for setting (dividing) teeth, the cutter is set in motion upon the support
and the article to be toothed secured either between the two centres or upon the
spindle. When the leading or guide-spindle is turned by means of a crank the
longitudinally sliding carriage with the cutter upon it is shifted, and the motion of
the spindle is conveyed by bevel-wheels to the change-spindle and by the worm and
the worm-wheel to the spindle. According to the number of teeth of the worm-
wheel the spindle will receive a more or less rapid revolving motion. This
arrangement is- the same as that first described only the rapid motion is here.
transmitted to the spindle. In both cases the worm must naturally be operated.
The peculiar feature of this arrangement is that according to the number of teeth
of the worm-wheel not only the desired angle of inclination or pitch of the spiral
groove may be predetermined, but by means of the division-disc and the index an
unusually great number of indentations may be cut.
Supposing, for example, that the worm is of ordinary pitch, that the worm-wheel
has 100 teeth and the division plate 100 divisions, whenever a tooth or groove is
cut and the lever with the index receive one turn (the index being displaced the
whole distance of 100 divisions upon the graduated plate) the blank will receive a
similar number of divisions or in other words 100 grooves or teeth, as the case may

page_text: be.
If the index is moved but one division upon the graduated plate and the lever
is moved 100 times in succession together with the index the worm-wheel will have
advanced one tooth-space, and when the lever with the index has been caused to
make 100 times 100 movements, .e. when it has been moved 10,000 times the
distance of one division, the worm-wheel will during this time have completed one
revolution, and the blank will have received 10,000 indentations. Thus according
to the number of divisions or spaces the lever with the index pass at each movement,
after one groove or tooth has been cut in the blank, the pitch of such grooves or
teeth can be varied to a large extent which may still be increased by additional
worm-wheels being passed on the spindle.
In cutting straight grooves it is sufficient to tighten the change-spindle by means
of nuts and to throw the bevel-wheels out of gear.
For making spiral drills with inclined convolutions the worm-wheel is bored
eccentrically and mounted upon a counter-shaft.
To obtain spiral convolutions of a gradually rising pitch in a drill, it is necessary
to throw the worm into gear with that point of the worm-wheel which is nearest to
the centre of the counter-shaft.
The material of which the drill is to be made should be fixed by means of a
chuck upon the spindle and located within a guide-way. When the leading screw-
spindle.is, set in motion, which may be effected either directly or indirectly by
means of a cord, this spindle moves the carriage or slide with the cutters adjustably
arranged upon it, along the cheek of the machine, and at the same time, through
the medium of double wheels, turns the change-spindle. This spindle by means
of the worm and worm-wheel transmits the motion to the counter-shaft from
which again by means of worm-wheels motion is imparted to the lathe-spindle.
Owing to the eccentric arrangement of the worm-wheel the rotation of the spindle
becomes irregular while that of the guiding-screw spindle remains uniform.
The relation of 1 to 2 existing between the shaft and the screw spindle has for
its object to ensure that the spiral groove completes at least one revolution during
the time that the worm wheel makes one half of a revolution. A rail serves to
raise and lower the two sliding cutter carriers at the same time, so that the grooves
in the spiral drill are gradually flattened down.
In a machine arranged for under-cutting tools on the sides the pulley through
which the mechanism is operated, is loosely mounted upon the spindle upon which
is fixed the first, gear wheel which gears with the change-wheels. The last of
these wheels is firmly secured upon a shaft and bevel gearing is adjustable upon
the change-spindle, so that either of these wheels may as required be thrown into
gear with the bevel-wheel for the purpose of imparting motion to the change-
spindle and through it to the spindle either to the right or to the left as the case
may be.
The worm gearing with the worm-wbeel is firmly mounted upon the change-
spindle, and the worm-wheel upon the spindle is exchangeable.
The motion of the pulley is transmitted by the wheels to the coupling shaft from
which through the medium of the first bevel-wheel and either of the other bevel-
wheels it is conveyed to the worm and from this by means of the worm-wheel to
the spindle. In addition to this and at the same time other wheels transmits the
motion of the said offset pulley by means of the shaft and of a universal joint to
another pulley capable of revolving together with a bearing or socket firmly secured
to, the longitudinally sliding carriage. Upon this carriage a part is arranged to
oscillate with the carrier. The pulley is provided with a curved groove in which
engages a pivot and roller arranged on a projecting tappet.
The curved groove is so shaped that at each revolution of the pulley, owing
to the sliding of the pivot and roller in the groove, the part supporting the cross-
carrier is once swung round upon the sliding carriage. The leading screw or
spindle is, at this junction disconnected from the coupling shaft and therefore
reinains inoperative. The spur wheels are provided with an equal number of teeth,
and so are also the bevel wheels so that by the time the pulley completes one
..

page_text: revolution, the worin and the other pulley have also made one turn while the
speed of rotation of the spindle depends on the number of teeth of the worm
wheel.
To undercut a number of cutter teeth if the worm has five convolutions, it is
necessary to place upon the spindle a worm wheel with a number of teeth five
times greater than that of the cutter to be manufactured. Supposing, for example,
that it is desired to undercut a tool with ten cutting teeth, the worm having five
convolutions, a worm wheel with 10 × 5 50 teeth should be passed upon the
spindle. In this case the worm which, at each revolution, causes the worm
wheel to advance five tooth spaces must complete 10 revolutions, and the cross-
carrier swings or rocks 10 times, during the time that the worm wheel completes
one revolution. Thus in undercutting each individual cutter-tooth, the cross-carrier
makes one oscillating movement, .e. once swings backwards and forwards upon the
carriage. To underent tools with any other number of cutter-teeth, worm wheels
having the corresponding number of teeth must therefore be mounted, upon the
leading screw.
The same undercutting machine may be so constructed that the cross-carrier
instead of oscillating automatically is adapted for rectilinear automatic motion,
but is also capable of revolving for the purpose of undercutting beads and spheres.
Except as regards the motion of the carrier the arrangement of the machine is in
this case identical with that just described.
The cross-carrier is here fitted to revolve by means of a worm and the worm
wheel.
The worm wheel is fast upon the stock of the support, and the worm is fixed
upon the shaft revolvably supported by a movable piece and provided with a
crank.
The movable piece is gripped upon the longitudinally sliding carriage the pulley
with its curved groove is revolvably supported by a bearing attached to the said
movable piece. A bell-crank lever pivotted to the lug of the movable piece and
one arm of which forms a toothed sector while its other arm carries a pivot and
roller, engages with the roller in the curved, groove of the pulley and with the
sector in the rings of a rod or bar. The end of this rod passing through the
stock of the carrier which stock is pivotted in the movable piece is, by means
of a pin and slot movably connected with one arin of the bell-crank lever.
The other arm of the bell crank lever carries a ball bearing for the screw spindle
serving to shift the supporting carriage. The cross-slide may thus be displaced
without necessitating another similar slide. While the pulley rotates, -as it does
in the first described arrangement, the pivot of the bell-crank lever slides in a
groove, and at each revolution the groove causes the said bell crank lever first to
turn slowly about its pivot in one direction, and then swiftly back, and through the
action of the toothed segment, the bar or rod is moved longitudinally, and
the bell-crank lever turns once and moves the slide or carriage of the cross-
support with the shaping. tool, once slowly towards the blank, and then
quickly back.
For undercutting beads, the carrier with the shaping tool is by the worm and
worm wheel carried round the blank, in the movable piece. It should be observed
by the way that in thus finishing the beads, their size is diminished, while the circles
continue precisely the same.
To copy and undercut automatically a cutter or any other tool, I provide a
copying mechanism in addition to the arrangement previously described, by which
the spindle and the pulley with a curved groove are operated for undercutting
purposes. With a view to copying-work the movable part of the cross-carrier is
arranged to turn upon the longitudinally sliding carriage in accordance with a
pattern plate. The pattern is rigidly connected with a worm wheel mounted upon
a stock of the cross-carrier passing through the movable part. Upon the carriage
are secured two rings connected by a rod between which the movable piece may be
turned to the desired position upon the carriage.

page_text: In the centre of the connecting rod is situated a roller in contact with which the
pattern is arranged to move. The shape of the pattern of course varies according
to the article to be produced, so that as the said pattern moves against the said
roller, the cross-carrier is correspondingly turned upon the longitudinally. sliding
carriage.
For the purpose of operating the pattern moving or adjusting the longitudinal
slide by means of the leading screw-spindle the shaft is provided with a driving
pulley and worms.
The rotary motion if imparted to this shaft is transmitted through the worm and
worm wheel, and through the medium of the change-gear contained in the casing to
the leading screw spindle and at the same time, through the other worm and worm
wheel and also through the medium of the change-gearing enclosed in the casing to
the shaft and from the shaft by means of wheels to the shaft, universal joint, worm,
worm wheel and pattern. The relation of the motion of the longitudinal slide to
the rotation of the pattern should be such that the said slide moves a distance equal
to the width of the blank, whenever the pattern has made one turn.
For undercutting, the reciprocating motion of the sliding carriage upon the cross-
carrier is derived from the pulley in a somewhat more simple manner than in the
arrangement before described. For this purpose there is pivotted to a bridge
provided upon the cross-carrier a lever carrying the ball-bearing for the screw-
spindle, a pivot and roller, engaging in the groove of the pulley; so that at each
revolution of the pulley by means of this lever the slide is directly shifted the
cross-carrier.
upon
The automatic undercutting and copying of tools in this machine are effected as
follows:-
Supposing that it is required to shape a cutter-head with ten teeth, the under-
cutting to extend over a width of 50 millimetres. The blank is first secured
between the spindle-stock and the sliding poppet. The spindle and the pulley with
the curved groove are operated from the pulley in the same way as in the case
mentioned before of undercutting a cutter-head with ten teeth. Similarly, in the
operation of the spindle and of the pulley the relation of transmission of motion is
the same as before as the cutter-head in this instance has the same number of teeth
as that previously referred to.
The pattern and leading-screw or spindle whereby the carriage is moved
longitudinally receive motion from the shaft. Whenever the pattern or the worm
wheel completes one revolution the longitudinally sliding carriage must have moved
a distance of 50 millimetres. Supposing now that the leading screw has a pitch of
5 millimetres, one revolution of it will move the carriage a space of 5 millimetres ;
and it is therefore necessary for this screw to turn ten times in order to move the
carriage 50 millimetres.
= 100
If the worm-wheel has 50 teeth, and the worm 5 convolutions, it follows (since
10 × 50
the bevel-wheels in the case are equal in size) that the shaft will make
5
revolutions, during the time that the leading screw makes 10 revolutions. While
therefore the shaft makes 100 revolutions the pattern will complete one revolution
and if the worm has 5 convolutions and the first worm one convolution, and the
second worm wheel has 50 teeth; and if furthermore motion is transmitted from,
the change-gearing enclosed in the case and from the toothed wheels to the pattern
by means of the universal joint, it' is necessary to pass upon the spindle a worm-
wheel with 40 teeth.
In screw-thread cutters the undercutting is effected not by a turning operation,
but by an actual cutting operation, and in a perfectly automatic manner.
The arrangement is mainly the same as that described in connection with the
first form of undercutting machine with the only difference that here the turning
spindle is operated directly and that instead of a turning tool, a cutter head is used
which may be adjusted at any desired angle to the blank.
The spindle is operated by means of a pulley a worm and a worm-wheel from

page_text: which motion is further transmitted through another worm, worm wheel and change-
wheels to the leading screw and through the medium of wheels to the shaft with
the pulley having the curved groove.
The relation of the gearing through which motion is communicated from the
spindle to the shaft is as 1:3 so that while the spindle completes one revolution
the pulley makes three revolutions. The relation between the dimensions of the
respective gear-wheels of the spindles depends on the pitch of the thread to be cut
and is obtained by passing a worm-wheel with a corresponding number of teeth
upon the change-spindle.
The shaft is provided with a spiral groove of a pitch equal to that of the cutting
groove with which the screw-thread cutter is to be provided.
In this groove engages a spring attached to the pulley which in consequence
turns along with the shaft and when the slide is moved longitudinally by the screw-
spindle this pulley by making its spring slide within the said groove becomes
displaced upon the shaft and at the same time moves in a direction corresponding
to the shape of the groove.
In the curved groove of the pulley engages by means of its roller, the lever
provided with a ball bearing which lever, similarly to the lever as the pulley
revolves, sets in motion the cross-carrier. The pivot is here eccentrically situated
upon a bolt located in the movable piece.
With the bolt is rigidly connected a lever carrying a roller at its free end,
engaging in a groove of the rail or rod so that when the longitudinal slide is moved
by the leading screw, the said roller runs in the groove of the rod.
The groove is somewhat curved at its closed end and then extends further on a
straight line.
The rail serves for continuously cutting screw-thread cutters the first part of
which is somewhat tapering in shape while the remaining portion is cylindrical.
This result is obtained by so adjusting the slide during the initial stage of the
cutting operation that the roller is brought to the curved part of the groove of the
rail or rod; and when the slide is shifted by the leading screw,aid roller
passes on, from the curved, into the straight portion of the groove; while at the
same time, through the medium of the lever the bolt together with the pin is also
gradually shifted to a limited extent, whereby the cross-carrier under the action of
the lever is slowly driven outwardly with a view to cutting the tapering part of the
screw-thread cutter. Then, as the roller proceeds further in its course, the cutting
of the cylindrical portion of the tool is performed.
The cutter-spindle is operated by means of a pulley from the shaft which,
through the medium of gear-wheels, a shaft and bevel-wheels turns the said cutter
spindle. This special operating device is provided in order to enable the cutter to
be precisely adjusted to suit the angle of the pitch of the screw-drill to be cut,
independently of the other parts of the machine. To facilitate this adjustment
there is arranged upon the carrier a cylinder provided with worm teeth with which
gears a worm which, though capable of revolving, may be tightly locked in position
in its bearing.
With this cylinder is rigidly connected the bearing of the cutter-spindle, and the
shafts serving to operate this spindle, are so embedded in the said cylinder, that
the revolving pin of the cylinder coincides with the axis of the shaft and forms an
extension thereof through the centre of the cutter. The adjustment of the cutting
tool is conveniently and accurately effected by giving a corresponding turn to the
cylinder by ineans of a crank and a worm which adjustment is moreover facilitated
by an index or pointer arranged upon the cylinder, while its bearing is fitted by a
graduated scale.
This arrangement enables a screw-cutting tool or drill to be cut to the finest
pitch with the utmost precision.
Hitherto screw-cutters have been either simply turned in a lathe or undercut.
These methods, however are inaccurate and have the additional inconvenience of

page_text: mg capensive, so nas muerent screw-cutters could only to a very limited extent
be employed.
Motion may be imparted to the turning or cutting spindle either directly ie
without passing additional wheels thereon (at a rate of speed varying as required).
or indirectly.
This arrangement consists in the eccentric situation of the worm so that it may
be thrown into gear with several worm wheels in succession.
Motion is here conveyed by means of the cord pulley to the shaft rigidly
connected with the worm. This shaft is adapted to revolve in the two eccentrics
located in the spindle-stock, each on one side of the worn, and connected with
each other. The connection is formed by a crank arranged above the worm which,
hovever, does not interfere with the worm-wheels being thrown into gear with the
said worn.
This gearing is further facilitated by the adjustable arrangement of
the worm wheel upon the coupling shaft. The throwing into gear of the worm
with either of the wheels is effected by giving a turn to the eccentrics in the spindle-
stock by means of a lever. When the worm is in gear with one worm-wheel the
turning-spindle is operated from the shaft through the medium of the counter-shaft
change-wheels, worm and worm-wheel, the operation being similar to that of some
previously described arrangements, and when the worm is in gear with the other
worm-wheels the turning-spindle is directly operated from the shaft.
The cutter may be constructed on the principle of a revolver-barrel, but fitted to
carry out various descriptions of work according to requirements. This cutter is
arranged upon the carrier of the universal machine instead of the usual tool-holder
carrying but one tool at a time.
There may be employed in the machine either two revolver-heads, or one
revolver-head in conjunction with an ordinary tool holder, upon which the tool is
locked by means of a clamp and screw; or again one revolver head arranged upon
the transverse carrier. The lower part of the revolver head is rigidly connected
with the slide of the cross-carrier in which is also secured a bolt provided with a
steep-pitched screw-thread at its upper or free end.
Upon the bolt is placed a spring and the top part rests upon the said spring.
This top part overlaps the lower part and is guided by the bolt and by its edge
overlapping the lower part.
In the upper part there is implanted a number of pins equal to the number of
tools while the lower part is provided with a pin serving as a tappet or stop for the
pins of the top-part to impinge upon, which enables the tool or tools to be accurately
adjusted in relation to the axis of the blank. The top-part is moreover, provided
with lateral notches, in which the tools are fixed by means of screws. The hub or
boss of the key is provided with indentations on its periphery, in which engages
one end of a spring retained by hooks in the same recess in which is located the
boss the other end of the said spring being also suitably secured.
The tool is arranged in the operative position by shifting the revolver head
together with the slide, by means of the screw-spindle upon the cross-carrier. The
adjustment of the tools in relation to the axis of the blank is effected by means of a
set-screw provided on the sides of the upper part. These screws are arranged to
press upon a stop so that in operating by hand the attendant is at all times in a
position exactly to keep up the required measurements; while when the operation
is automatic, the mechanism may thus be reversed.
The tools are reversed by turning up the key by means of its nut upon the screw-
bolt, while the spring which had been compressed by the key being previously
screwed down, expands and grips the next tooth of the key. The spring situated
below the upper part at the same time raises this part sufficiently for the sides of
the pins to rise above the sides whereby the upper part is enabled to turn.
nut of the key is then screwed down again upon the bolt, whereby the spring which
engages with one of the teeth of the key is enabled to move the upper part along
with it to the position in which the next pin impinges against the stop. As the
The

page_text: said nut is still further screwed down, the upper part is moved down against the
lower part and the next tool is secured in its proper operative position.
Dated this 1st day of March 1892.
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to Turning Lathes and similar Tools.
I, WILHELM VOX PITTLER, of Maschinen-fabrik Gohlis-Leipzig, in the
Empire of Germany, 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 accompanying drawings are in the main representations of the universal
tool machine forming the subject of the British Patent No. 8374 of May 20, 1889,
though some of the settings or adjustments shown, are intended for work entirely
different from that specified in the said Patent, the means of operation being
however much the same, as will be seen.
On Sheet of the accompanying drawings, Figs. 1 to 3 represent a machine
for cutting right and left handed screw-threads.
Figures 4 and 5 show the arrangement by means of which two screw threads of
different pitch may be cut without any exchange of wheels.
This arrangement consists in mounting a wortn-wheel d on each end of the
change-spindle a, one of which wheels has a greater number of teeth than the
other.
In this machine the casing D with the change-spindle a is made capable of
revolving upon the leading screw C and the worm wheels d are fixed upon the
change-spindle a at such a distance from the centre of rotation, that by turning
the case D in one or the other direction, one or the other of the wheels d is thrown
into gear with the worin e. When the smaller worm wheel d is in gear with the
worm e, the change spindle a through the medium of the change-wheels and g
transmits a greater number of revolutions to the leading screw-spindle C, than
when the larger worm wheel is in gear with the worm e. In the former case the
slide-rest D' is in consequence moved more rapidly, and the pitch of the screw being
cut is increased.
Motion is transmitted by means of a speed-pulley to the spindle L to which
it is rigidly attached and to the leading screw C by means of the worm c, worm-
wheel d, change-wheel or 6 and wheel g.
Figures 6 to 9, Sheet 1, represent the arrangement for cutting spiral grooves,
cutters, rimers, worm-wheels, etc.
This arrangement consists of a division-plate or disc s rigidly attached to the
change-spindle a and of an arm or lever u with index or detent securely con-
nected with the worm e loose upon the spindle a which worm e gears with a worm
wheel & mounted upon the lathe spindle L.
The arm or lever u by means of the detent t may be set to any desired point
of the circumference of the division-plate or disc s.
When it is desired to employ the worm-wheel d and the worm e arranged in the
manner just described, in combination with the change-wheels, not only for cutting
but also for setting (dividing) teeth, the cutter is set in motion upon the support
and the article to be toothed secured either between the two lathe centres or upon
the spindle L. When the leading screw C is turned by means of a crank handle n
the slide-rest D' with the cutter upon it is shifted, and the motion of the leading
screw C is transmitted by bevel-wheels to the change-spindle a and by the worm e
and worm-wheel d to the spindle L. According to the number of teeth of the
worm-wheel the spindle L will receive a more or less rapid revolving motion.
This arrangement is the same as that shown in Figs. 1 and 2 only the rapid motion

page_text: is here transmitted to the leading screw C. In both cases the worm e must
naturally be operated. The peculiar feature of this arrangement is that according
to the number of teeth of the worm-wheel d not only the desired angle of inclina-
tion or pitch of the spiral groove may be predetermined but by means of the division
dise and the index or detent t an unusually great number of indentations may
४
be cut.
Supposing for example that the worm e is of ordinary pitch, that the worm-
wheel d has 100 teeth and the division plate s 100 divisions, whenever a tooth or
groove is cut and the lever or arm u with the index or detent receive one turn
(the detent & being displaced the whole distance of 100 divisions upon the graduated
plate or discs) the blank will receive a similar number of divisions or in other
words 100 grooves or teeth, as the case may be. If the detent is moved but one
division upon the graduated plate or disc and the lever or arm is moved 100
times in succession together with the detent & the worm-wheel d will have advanced
one tooth space and when the lever or arm a with the index or detent has been
caused to make 100 times 100 movements, i.e. when it has been moved 10,000 times
the distance of one division, the worm-wheel d will during this time have com-
pleted one revolution, and the blank will have received 10,000 indentations. Thus
according to the number of divisions or spaces the lever or arm u with the index
or detent t pass at each movement, after one groove or tooth has been cut in the
blank, the pitch of such grooves or teeth can be varied to a large extent which
may still be increased by changing the worm-wheel mounted on the spindle.
In cutting straight grooves it is sufficient to tighten the change-spindle a by
means of nuts m' and to throw the bevel-wheels out of gear.
Figures 10 to 13 on Sheet represent the invention applied to a machine for
making twist drills, with inclined convolutions, for which purpose the worm-wheel d
is bored eccentrically and mounted upon a counter-shaft.
In Figure 11 this machine is shown partly in elevation and partly in section,
Figure 10 being an end elevation, Figure 12 a section on line A A of Fig. 13,
and Fig. 13 a plan of the machine. To obtain spiral convolutions of a gradually
rising pitch, in a drill, it is necessary to throw the worm e into gear with that point
of the worm-wheel d which is nearest to the centre of the counter-shaft as
illustrated in Figure 10.
The material of which the drill is to be made should be mounted in a chuck L'
upon the spindle L and supported in a guide W.
When the leading screw C is set in motion, which may be effected either
directly or indirectly by means of a band ' this spindle C moves the carriage or
slide D with the cutters adjustably arranged upon it, along the bed-plate of the
machine and at the same time, through the medium of double wheels, turns the
change-spindle a. This spindle by means of the worm e and worm-wheel d
transmits the motion to the counter-shaft a from which again by means of
preferably skew gear wheels motion is imparted to the lathe-spindle L.
=
Owing to the eccentric arrangement of the worm-wheel d the rotation of the
spindle L becomes irregular while that of the leading screw C remains uniform.
The relation of 1 to 2 existing between the shaft and the lathe spindle L has
for its object to ensure that the spiral groove completes at least one revolution
during the time that the worm wheel d makes one half of a revolution. A. rail .J
serves to raise and lower the two sliding cutter carriers at the same time, so that
the depth of the grooves in the twist drill is gradually reduced.
Figures 14 to 17 on Sheet 3 represent a machine arranged for under-cutting tools
on the sides.
Figure 14 is a front view of this machine, Figure 15 is an elevation with the
bearing-case in section, Figure 16 a section on line OO of Figure 14, and Figure 17
a plan.
In this machine the speed pulley through which the mechanism is operated is
loosely mounted upon the spindle L upon which is fixed the first gear wheel
which gears with the change-wheel and through it with the wheels. The
1

page_text: wheels is firmly secured upon the shaft d' and the wheel f' as well as the bevel-
wheel g are rigidly secured on the leading screw shaft C. The bevel wheels b
are adjustable upon the change-spindle a so that either of these wheels may as
required be thrown into gear with the bevel-wheel g for the purpose of imparting
motion to the change-spindle a and through it to the spindle L either to the right
or to the left as the case may be.
The worm e gearing with the worm-wheel d is firmly mounted upon the change
spindle a and the worm-wheel d upon the spindle L is exchangeable.
9
The motion of the speed pulley is transmitted by the wheels ff and f to the
coupling shaft C' from which through the medium of the bevel-wheel and either
of the bevel-wheels bor it is conveyed to the worm e and from this by means of
the worm wheel d to the spindle L. In addition to this and at the same time the
wheel gearing with the wheel transmits the motion of the said speed pulley ²
by means of the shaft d' and of a universal-jointed shaft to a cam disc gcapable
of revolving in a bearing carried in a supporting arm D' mounted on the longitu-
dinally sliding carriage or slide rest D. Upon this carriage D' a part Ď³ is
arranged to oscillate with the carrier D². The cam disc g provided with a
groove in which engages a roller arranged on an arm projecting from the
piece D.
The cam groove is so shaped that at each revolution of the disc g' owing to the
engagement of the roller in the groove, the part D³ supporting the cross-carrier is
oscillated once upon the sliding carriage D¹. The leading screw or spindle C is,
at this juncture, disconnected from the coupling shaft C' by means of the clutch
shown in Fig. 18 and therefore remains inoperative.
The spur wheels ff and f³ are provided with an equal number of teeth and so
are also the bevel wheel gb and so that by the time the speed pulley 2 com-
pletes one revolution the worm e and the cam disc g' have also made one turn,
while the speed of rotation of the spindle L depends on the number of teeth of
the worm-wheel.
=
To back off a number of cutter teeth, if the worm e has five convolutions, it is
necessary to place upon the spindle L a worm wheel & with a number of teeth five
times greater than that of the cutter to be manufactured. Supposing for example
that it is desired to back off a tool with ten cutting teeth, the worm e having
50 teeth should be provided upon
five convolutions, a worm wheel with 10 × 5
the spindle. In this case the worm e which at each revolution, causes the worm
wheel to advance five tooth spaces, must complete 10 revolutions, and the cross-
carrier D swings or rocks 10 times, during the time that the worm wheel d com-
pletes one revolution. Thus in backing off each individual cutter-tooth, the
cross-carrier D' makes one oscillating movement, i.e. once swings backwards and
forwards upon the carriage D', or it may be simply shifted instead of oscillated.
To back off tools with any other number of cutter-teeth, worm-wheels having the
corresponding number of teeth must therefore be mounted upon the spindle L.
Figures 18 to 22, Sheet 4, represent the same backing off machine so con-
structed that the cross-carrier D² instead of oscillating automatically, is adapted
for automatic rectilinear motion and it is also capable of revolving in the socket
piece D³ for the purpose of backing off the rounded edges of rotary cutters beads
spheres and the like.
Figure 18 is an elevation of the machine with the headstock in section.
Figure 19 is section of the cheek on line Q Q of Fig. 18. Figure 20 is a vertica
section of the carrier. Figure 21 shows part of the machine in plan and
Figure 22 is a longitudinal section on line T T of Figure 20.
Except as regards the motion of the carrier D', the arrangement of the machine
is in this case identical with that just described with reference to Figs. 14 to 17.
The cross-carrier D' is here fitted in the socket piece D' to revolve by means of
the worm e and the worm wheel d².
This worm wheel d is fast upon shaft of the support D' passing through the

page_text: movable socket piece D³, and the worm e¹ is fixed upon the shaft a' revolvably
supported by said movable socket piece D³ and provided with a crank handle.
The socket piece D³ is gripped upon the longitudinally sliding carriage D¹. The
cam disc g with its curved groove is revolvably supported by a bearing attached
to the said socket piece D³.
The bellcrank lever k¹ is pivotted at to the lug of the movable socket piece D³,
and one arm of forms a toothed sector, while its other arm carries a pivot and
roller which engages with the groove of cam g'; the sector arm of k engages with
the annular projections or rings of a rod or bar o². The end of this rod o² passing
through the shaft of the carrier D2 which shaft is pivotted in the movable socket
piece D³, is, by means of a pin and slot movably connected with one arm of the
bellcrank lever pivotted at .
The other arm of the bellcrank lever k carries a ball bearing for the screw
spindle C² serving to shift the supporting carriage. The cross slide may thus be
displaced without necessitating another similar slide. While the pulley g¹ rotates-
as it does in the first described arrangement-the pivot of the bell-crank lever A¹
slides in a groove and at each revolution the groove causes the said bell-crank
lever first to turn slowly about its pivot in one direction, and then swiftly back,
and through the action of the toothed segment the bar or rod o² is moved longi-
tudinally, and the bellcrank lever turns once about r and moves the slide or
carriage of the cross-support D2 with the shaping tool, once slowly towards the
blank, and then quickly back.
For undercutting beads the carrier D2 with the shaping tool is by the worm el
and worm wheel carried round the blank in the movable socket piece D³. It
should be observed by the way that in thus finishing the beads, their size is
diminished, while the circles continue precisely the same.
Figs. 23 to 29, Sheets 5 and 6, show a machine for both backing off and copying
cutters and other tools.
Figure 23 is a front view thereof with the change-gear casings E¹ and F¹
in section. Figure 24 is a side view of the machine with the change-gear
casings D and E¹ in section on line M M of Figure 23. Figure 25 is a
section on line N N of Figure 23. Figure 26 is a back view of the cross-carrier.
Figure 27 is a section on line V V of Fig. 23 with the cross-carrier in elevation.
Figure 28 is a plan with the change-gear casing F¹ in section and Figure 29 is a
section on line W W of Figure 23 with the cross-carrier in elevation. Figures 30
and 32 represent two blanks cut from a pattern, and Figures 31 and 33 show the
pattern plates for the said blanks at a reduced scale.
To copy and back off automatically a cutter or other tool, I provide a copying
mechanism in addition to the arrangement described with reference to Figures 14
to 22, by which the spindle L and the grooved cam disc g¹ are operated for backing
off purposes.
With a view to copying work the movable part D³ of the cross-
carrier D³ is arranged to turn upon the longitudinally sliding carriage or slide-
rest D' in accordance with a pattern plate or disc. The pattern plate or disc is
rigidly connected with the worm wheel d mounted upon the shaft of the cross
carrier D2 passing through the movable part D³. Upon the carriage D' are
secured two rings connected by a rod between which the movable piece D³
may be turned to the desired position upon the carriage D'.
In the centre of the connecting rod is situated a roller h³ in contact with
which the pattern plate 4 is arranged to move. The shape of the pattern plate A
of course varies according to the article to be produced so that as the said pattern
plate moves against the said roller ³, the cross-carrier is correspondingly turned
upon the longitudinally sliding carriage D'.
For the purpose of operating the pattern plate and moving or adjusting the
longitudinally sliding carriage or slide-rest D¹ by means of the leading screw
spindle C the shaft C³ is provided with a driving pulley o and worms e² and e³.
The rotary motion imparted to this shaft C3 is transmitted through the worm e³

page_text: and worm wheel d' and through the medium of the change gear contained in the
casing F to the leading screw or spindle C, and at the same time through the
worm and worm wheel d³ and also through the medium of the change gearing
enclosed in the casing E¹ to the shaft , and from the shaft 2 by means of the
wheels and to the shaft'm, universal jointed shaft 3, worm e, worm-wheel d³
and pattern plate k. The relation of the motion of the longitudinal slide or
slide-rest D' to the rotation of the pattern plate should be such that the said
slide D' moves a distance equal to the width of the blank whenever the pattern
plate has made one turn.
For backing off the reciprocating motion of the sliding carriage or slide rest
upon the cross-carrier D is derived from the cam disc g' in a somewhat more
simple manner than in the arrangement before described and shown in Figs. 18
to 22. For this purpose there is pivotted to one or two bracket arms u² provided.
upon the cross-carrier D' a lever carrying the ball bearing for the screw
spindle C and a pivot and roller, engaging in the groove of the cam disc g', so
that at each revolution of the cam disc by means of this lever ³ the slide is
directly shifted upon the cross carrier D."
The automatic backing off and copying of tools or other articles in this machine
are effected as follows,-
Supposing that it is required to shape a cutter-head with say ten teeth, the
backing off to extend over a width of 50 millimetres. The blank is first secured
between the lathe centres. The spindle L and the cam disc g' are operated from
the speed pulley in the same way as in the case mentioned before of backing off a
cutter-head with ten teeth. Similarly, in the operation of the spindle L and of the
cam disc the relation of transmission of motion is the same as before, as the
cutter-head in this instance has the same number of teeth as that previously
referred to.
The pattern plate and leading-screw or spindle C whereby the carriage or
slide rest D' is moved longitudinally receive motion from the shaft C³. Whenever
the pattern plate or the worm-wheel d completes one revolution the longi-
tudinally sliding carriage D' must have moved a distance of 50 millimetres.
Supposing now that the leading screw C has a pitch of 5 millimetres, one revolution
of it will move the carriage D' a space of 5 millimetres; and it is therefore
necessary for this screw C to turn ten times in order to move the carriage
50 millimetres.
5
If the worm-wheel d has 50 teeth, and the worm e³ 5 convolutions, it follows
(since the bevel-wheels in the case are equal in size) that the shaft C³ will
10 × 50
make.
= 100 revolutions, during the time that the leading screw C makes
10 revolutions. While therefore the shaft C³ makes 100 revolutions the pattern
will complete one revolution and if the worm e² has 5 convolutions and the first
worm one convolution, and the second worm-wheel has 50 teeth, and if
furthermore motion is transmitted from the change-gearing enclosed in the case E
and from the toothed wheels ff to the pattern plate by means of the
universal joint, it is necessary to pass upon the spindle a² a worm-wheel with
40 teeth.
Figures 34 to 43 Sheet 7 and 37 and 37B Sheet 8 represent a machine for
making screw-thread cutters or taps. The backing off of these tools is effected by
a rotating cutter and in a perfectly automatic manner. The arrangement is mainly
the same as that described in connection with the first form of backing off
machine with the only difference that here the turning spindle is operated directly
and that instead of a turning tool a cutter-head or rotating cutter is used which
may be adjusted at any desired angle to the blank.
Figure 34 is an elevation; Figure 35 an end view with the change gear casing D
in section; Figure 36 is a side view of the longitudinal slide and cross-carrier
partly in section on line X X of Figure 34. Figure 37 is a plan with the spindle-
stock and the cross-carrier in section on line Z Z of Figure 34. Figure 38 is a

page_text: section on an enlarged scale on line Y Y of Figure 34; and Figure 39 is a section
on line R R of Figure 38. Figure 40 is an elevation of the rail used for conic
cutting or bevelling and Figure 41 represents a spiral backed off screw thread.
Figure 42 is a section of the same before cutting the groove and Figure 43 is a
similar section after cutting the groove.
The spindle L is operated by means of a pulley a worm e and a worm-
wheel d and from the spindle L motion is further transmitted through the
worm e, worm-wheel d and change-wheels bb₁ and y to the leading screw C, and
through the medium of wheels fff and f³ to the shaft with the grooved cam
disc g¹.
The relation of the gearing and f³ through which motion is communicated
from the spindle L to the shaft is as 1:3 so that while the spindle L completes
one revolution the cam disc g' makes three revolutions. The relation between
the dimensions of the respective gear-wheels of the spindles L and C depends on
the pitch of the thread to be cut and is obtained by mounting a worm-wheel d
with a corresponding number of teeth upon the change-spindle a.
The shaft is provided with a spiral groove of a pitch equal to that of the
cutting groove with which the screw-thread cutter is to be provided.
In this groove engages a key or feather attached to the cam disc g¹ which in
consequence turns along with the shaft 2 and when the slide D¹ is moved longi-
tudinally by the screw-spindle C this cam disc by its key or feather sliding within
the said groove becomes displaced upon the shaft and at the same time moves in
a direction corresponding to the shape of the groove.
In the groove of the cam disc g engages by means of its roller, the lever ³
provided with a ball bearing and pivotted at s', which lever, similarly to the
lever (Figure 25), as the cam disc g revolves, sets in motion the cross carrier.
The pivot is here eccentrically situated upon a bolt s located in the movable
piece D³.
With the bolts is rigidly connected a lever or arm 4
its free end, engaging in
a groove of the rail or rod
longitudinal slide D₁ is moved by the leading screw C, the
groove of m².
carrying a roller /* at
m², so that when the
said roller runs in the
As shown in Fig. 4º the groove of m³ is somewhat curved at its closed end and
then extends further in a straight line.
The rail m² serves for continuously cutting screw-thread cutters or taps the first
part of which is somewhat tapering in shape while the remaining portion is
cylindrical. This result is obtained by so adjusting the slide D¹, during the
initial stage of the cutting operation, that the roller is brought to the curved
part of the groove of the rail or rod m³, and when the slide D is shifted by the
leading screw C, the said roller passes on, from the curved into the straight portion
of the groove; while at the same time through the medium of the lever or arin k³
the bolts together with the pivot pin s¹ is also gradually shifted to a limited extent
whereby the cross carrier D² under the action of the lever is slowly driven
outwardly with a view to cutting the tapering part of the screw-thread cutter.
Theu, as the roller proceeds further in its course, the cutting of the cylindrical
portion of the tool is performed.
The cutter-spindle is operated by means of preferably a sheave pulley from
the shaft which through the medium of gear wheels o³ of a shaft and bevel
wheels turns the said cutter spindle . This special operating device is
provided in order to enable the cutter to be precisely adjusted to suit the angle of
the pitch of the screw-tap to be cut, independently of the other parts of the
machine. To facilitate this adjustment there is arranged upon the carrier D² a
cylindrical block y' provided with worm teeth with which gears a worm es, which,
though capable of revolving, may be tightly locked in position in its bearing.
Within this cylindrical block y' is provided the bearing of the cutter spindle and
the shafts serving to operate this spindle are so mounted in the said block that
the horizontal centre of rotation of the block y' coincides with the axis of the

page_text: shaft and passes through the centre of the cutter. The adjustment of the cutting
tool is conveniently and accurately effected by means of a crank handle n' and
worm e, which adjustment is moreover facilitated by an index or pointer arranged
upon the cylindrical block, working over a graduated scale on the bearing of
the block.
As shown in Figures 37 and 37° the shafts L and 12 may be operated by one
common shaft the worm and worm wheels being adjusted and reversed
accordingly whereby the required division for undercutting is obtained.
Figure 37 is a front view partly in section on line ab of Figure 37" which
latter is a vertical section on line ab of Figure 37.
The operation is as follows,-
While under the action of the shaft e, the shaft or spindle L completes one
revolution, its worm being threaded singly; it will with a worm such as
having
a thread of three times the pitch cause the shaft to complete three revolutions
during the same time that I completes one.
This arrangement enables a screw cutting tool or drill to be cut to the finest
pitch with the utmost precision.
Hitherto screw cutters or taps have been either simply turned in a lathe or
backed off. These methods, however, are inaccurate and have the additional
inconvenience of being expensive, so that backed off screw-cutters could only to a
very limited extent be employed.
Figs. 44 to 47, Sheet 9, represent the head-stock of a machine in which according
to requirements motion may be imparted to the turning or cutting spindle either
directly ie. without applying additional wheels thereto (at a rate of speed varying
as required), or indirectly.
Figure 44 is an elevation of this head stock. Fig. 45 is a view partly in
section on line H H of Fig. 44 and partly in elevation. Figure 46 is a plan
partly in section on line F F of Fig. 44, and Figure 47, drawn to a smaller scale
than Figs. 44, 45 and 46, is a vertical longitudinal section thereof and of a
portion of the bed-plate.
This arrangement consists in the mounting of the worm & eccentrically so that
it may be thrown into gear with several worm wheels and »³.
gear
Motion is here transmitted by means of the pulley to the shaft K', rigidly
connected with the worm 3. This shaft K¹ is adapted to revolve in the two
eccentrics p' located in the head-stock, each on one side of the worm and connected
with each other. The connection is formed by a frame arranged above the worm s³
which, however, does not interfere with the worm wheels and being thrown
into
with the said worm. This gearing is further facilitated by the adjustable
arrangement of the worm-wheel upon the coupling shaft C'. The throwing into
gear of the worn with either of the wheels is effected by giving a turn to
the eccentrics in the head stock by means of a lever handle '.
worm is in gear with worm-wheel the lathe spindle L is operated from the
shaft through the medium of the counter-shaft C, change-wheels and g,
worm e and worm-wheel d, the operation being similar to that of arrangements
shown in Figs. 10 to 29; and when the worm is in gear with the worm-wheels³
and, the turning spindle L is directly operated from the shaft K', as previously
described in reference to Figs. 34 to 40.
.
When the
Figures 48 to 57, Sheet 9, represent a cutter constructed on the principle of a
revolver-barrel, but fitted to carry out various descriptions of work according to
requirements. This cutter is arranged upon the carrier of the universal machine
instead of the usual tool-holder carrying but one tool at a time.
Figure 48 is a front view of a double revolver-cutter. Fig. 49 is a side view.
Fig. 50 is a plan. Fig. 51 is a section on line PP of Fig. 49. Fig. 52 is a
vertical longitudinal section thereof on an enlarged scale, with part of the cross
carrier. Fig. 53 is a horizontal section thereof on line B B of Fig. 52, and Fig. 54
a horizontal section on line U U of Fig. 52. Fig. 55 is a side view, Fig. 56 a
plan and Fig. 57 a back view of a revolver-head combined with a cutting off tool.

page_text: There may be employed in the machine either two revolver-heads, as shown in
Figs. 48 to 50, or one revolver-head in conjunction with an ordinary tool-holder,
upon which the tool is locked by means of a clamp and screw or one revolver-
head only may be arranged upon the transverse carrier D³. The lower part of the
revolver-head is rigidly connected with the slide of the cross-carrier D², in which
is also secured a bolt m provided with a steep-pitched screw-thread at its upper or
free end.
Upon the bolt m is placed a spring m³ and the top part rests upon the said
spring. This top part y overlaps the lower part and is guided by the bolt m* and
by its edge overlapping the lower part.
In the upper part y there are fitted a number of pins equal to the number of
tools 3, while the lower part is provided with a pin, serving as a tappet or stop
for the pins of the top part to impinge upon, which enables the tool or tools 1³ to
be accurately adjusted in relation to the axis of the blank. The top part y³ is
moreover, provided with lateral recesses in which the tools 3 are fixed by means
of screws y².
The hub or boss of the key p² is provided with indentations or teeth on its
periphery, in which engages one end of a spring retained by hooks or equivalent
in the same recess in which is located the boss; the other end of the said spring 7'
being also suitably secured at y².
The tool is arranged in the operative position by shifting the revolver head
together with the slide, by means of the screw-spindle C², upon the cross-carrier D².
The adjustment of the tools 3 in relation to the axis of the blank is effected by
means of a set-screw provided on the sides of the upper part y³. These screws
are arranged to press upon a stop y³ so that in operating by hand, the attendant is
at all times in a position exactly to keep up the required measurements, while, when
the operation is automatic, the mechanism may thus be reversed.
The tools are reversed by turning the key p² by means of its nut upon the screw
bolt m while the spring which had been compressed by the key p² being
previously screwed down, expands and grips the next tooth of p². The spring m³
situated below the upper part y³ at the same time raises this part y³ sufficiently for
the sides of the pins to rise above the sides of s, whereby the upper part y³ is
enabled to turn.
$3
The nut of 2 is then screwed down again upon the bolt m' whereby the spring g'
which engages with one of the teeth of p² is enabled to move the upper part y³
along with it to the position in which the next pin impinges against the stop s¹.
As the said nut is still further screwed down, the upper party³ is moved down
against the lower part and the next tool is secured in its proper operative position.
On Sheet II of the drawings is represented a cutter-head (herein termed a
"revolver") adapted to receive a greater number of tools than that last described.
Fig. 58 is an elevation thereof, Fig. 59 is a vertical section on line a b of Fig. 58
aud Fig. 60 a horizontal section on line c d of Fig. 59.
This cutter head mainly consists of a casting e having a central perforation and
revolvably fitted to the circular carriage or slide D¹.
The tools are fitted therein in any desired manner.
arranged to receive ten tools.
The revolver here shown is
The arrangement for reversing motion is as follows,-The lever has a ring g
integral with it, and is adapted to turn upon the projection or boss of the revolver-
heade and it is provided with a pawl which engages with the ratchet teeth i.
By turning the lever the pin k is at the same time removed from the perforation
of the head by means of a cam surface f" formed on the periphery of the circular
part off bearing against the radial pin f* the inclined end of which engages with
the side of a slot in the pink as shown in Figure 60.
When however the lever f
is moved back the revolving head e is shifted a distance of one or more divisions,
the pin being caused by the spiral spring 1 to re-enter and lock the revolver in
position again. The screw m serves as a stop for the lever f.
Figures 61 to 64 on Sheet 12 represent a rotary cutter-table or work support

page_text: specially arranged for plane work. This arrangement enables the blanks to be
secured in position on the table while the machine operates without interruption.
Figure 61 is a side elevation of the table, Fig. 62 is a rear view thereof, Fig. 63
is a vertical section on line ab of Fig. 61, also showing the parts operating
the table, and Fig. 64 is a plan.
C
The table e consists of preferably a casting which on its periphery or outer edge
is provided (in the present case) with surfaces grooved longitudinally for the recep
tion of bolts for securing the work to the table. The casting has a central
perforation which serves for fitting in a round revolving guide-carriage D'.
The table is operated by means of a worm d secured on the cutter-spindle and
imparting motion to the bevel wheel e the gear wheels and the hevel wheels y and h
by which the skew gear wheels i and are operated, the wheel & in its turn acting
upon the worn which is in gear with the worm-wheel m secured to the table.
The shaft is provided with a groove enabling the cutter-table to be displaced as
required.
It will be readily seen that the table e will slowly turn when the cutter spindle is
set in motion. The blanks fitted in position upon the said table are taken round
and in their circular course present themselves each in its turn to the action of the
cutter while such of them as are ready may be removed and replaced by fresh
blanks. If the table were provided with dividing mechanism it might be used for
cutting nuts as well.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is,
1. In a universal machine tool the arrangement of worm wheels d upon a change
spindle a whereby through turning the case D either of the said worm wheels may
be thrown into gear with the worm e for the purpose of cutting spirals of different
pitch without otherwise adjusting the machine substantially as described and
illustrated in the accompanying drawings.
2. In apparatus such as described the employment of change gearing in com-
bination with a worm and worm wheels and a graduated division plate or disc and
its index or detent for spiral cutting or threading and for dividing or "setting
the articles to be cut substantially as described and illustrated in the accompanying
drawings.
3. In apparatus such as described the eccentrically arranged worm wheel d
adapted to be driven by means of a worm e of corresponding pitch for the purpose
of cutting spiral grooves of a gradually varying pitch substantially as described
and illustrated in the accompanying drawings.
4. For backing off spiral drills cutters and the like the arrangement in which the
lathe spindle and backing off spindle are turned by means of worms and worm-
wheels whereby is obtained both a uniform cut and the desired backing off
substantially as described and illustrated in the accompanying drawings.
5. For copying or turning various articles to a given pattern the employment of
a revolving pattern plate substantially as described.
6. The inanufacture of screw-cutting taps with either spiral or straight backed
off grooves by means of a milling tool substantially as described..
7. For the ready and precise switching of the tools set in the revolver-head the
arrangement of a spring such as 'one end of which is secured to the upper part y³
while the other end by means of a hook grips the tooth on the boss or nave of a
key such as 2 which spring when the said key is screwed down carries the
upper part y down to a stop such as 8 and as the upper part y³ is further screwed
down upon the lower part the next tool is brought into the operative position
substantially as described and illustrated in Figures 48 to 54 of the accompanying
drawings.
8. The arrangement of a revolver-head in such a mauner that it may be turned
round in its own carriage in suitable guides for the purpose of enabling it to receive

page_text: a number of tools and of so arranging them that they are not in the way during
the operation of any one or more of them substantially as described and illustrated
in the accompanying drawings.
9. The arrangement of a table or work-support adapted for circular motion
about the longitudinally sliding carriage or slide rest substantially as described and
illustrated in Figures 61 to 64 of the accompanying drawings.
10. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 1, 2 and 3 of the
accompanying drawings.
11. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 4 and 5 of the
accompanying drawings.
12. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 6 to 9 of the
accompanying drawings.
13. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 10 to 13 of the
accompanying drawings.
14. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 14 to 17 of the
accompanying drawings.
15. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 18 to 22 of the
accompanying drawings.
16. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 23 to 33 of the
accompanying drawings.
17. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 34 to. 40 of the
accompanying drawings.
18. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 37 and 37 of the
accompanying drawings.
19. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 44 to 47 of the
accompanying drawings.
20. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 48 to 54 of the
accompanying drawings.
21. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 55 to 57 of the
accompanying drawings.
22. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 58 to 60 of the
accompanying drawings.
23. The combination and arrangement of parts constituting the complete
apparatus substantially as described and illustrated in Figures 61 to 64 of the
accompanying drawings.
Dated this First day of December 1892.
JULIUS WILHELM VON PITTLER.
W. P. Thompson & Boult,
Agents for the Applicant.