IMPROVEMENTS IN MACHINERY FOR CUTTING INDIA-RUBBER
Year: 1866

page_text: LETTERS PATENT to John Macmillan Dunlop and Frank Crossley, both
of Manchester, in the County of Lancaster, Engineers, for the Invention
of "IMPROVEMENTS IN MACHINERY FOR CUTTING INDIA-RUBBER."
Sealed the 14th May 1867, and dated the 16th November 1866.
PROVISIONAL SPECIFICATION left by the said John Macmillan Dunlop
and Frank Crossley at the Office of the Commissioners.of. Patents,
with their Petition, on the 16th November 1866.
We, JOHN MACMILLAN DUNLOP and FRANK CROSSLEY, both of. Manchester,
in the County of Lancaster, Engineers, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN MACHINERY FOR CUTTING INDIA-RUBBER,"
to be as follows:-
This Invention has for its object improvements in inachinery, for cutting
india-rubber. For these purposes an ordinary lathe, having a suitable. cutter
slide is used, to which the following improvements are applied.in order that
the cutter slide may be moved to and from its work more, advantageously. than
heretofore,. and also in order more conveniently, to accomplish the feed.. In
moving the cutter slide to and from its work it is desirable to cause, the cutter
to approach the work at a comparatively slow speed, and. that it should be
more quickly moved back from the work; this has before been proposed to be
accomplished in various ways.
According to the present Invention two screw or worm wheels are used on
two parallel shafts or axes which respectively receive continuous motion from
Dice S1

page_text: two worms or screws on a shaft at right angles to the two parallel shafts or
axes, above-mentioned, or the gearing may be otherwise arranged. The two
screws or other gearing are, by preference, arranged with their wheels in such
manner that one wheel is caused to make six revolutions to one revolution of
the other screw wheel, but this relation may be varied provided the proper
relation of their working be preserved. On the face of the wheel which makes
the greater number of rotations is a projection or pin, and in the wheel which
makes the lesser number of rotations there are fixed six projections or pins at
equal distances apart on one face of this wheel and near its outer circum-
ference. Between these two wheels is a shaft or axis having on it an arm
with two curved tails pointing in opposite directions; the pin or projection on
the one wheel acts on one of the curved tails, and the pins or projections on the
other wheel act on the other curved tail in succession. On the shaft or axis
of the arm with two curved tails there is an arm to which one end of a
connecting rod or link is attached, there being means of adjusting the position
of the end of the connecting rod or link to or from the centre of motion of the
arm. The other end of the connecting rod or link is attached to the cutter
slide; hence the cutter will be moved up to its work by the action of the
slower rotating wheel whilst the cutter slide will be brought back quickly by
the action of the pin or projection on the quicker rotating wheel.
In order to regulate the feed according to this Invention we employ
apparatus arranged as follows: A dividing plate is placed on the screw which
gives the cutter slide the motion necessary to commence the next cut; behind
this dividing plate is keyed a spur wheel which gears into a corresponding spur
wheel which is loose on the shaft or axis of the slower rotating screw wheel,
above mentioned, but such spur wheel is capable of being caused to rotate
with such shaft or axis by means of a friction or other proper clutch; on this
shaft or axis is keyed a cam which acts on one end of a lever by which the
clutch is caused for a time to fasten the spur wheel to its shaft or axis. The
other end of this lever carries a stud or point suitable to enter into the holes
in the divided plate, and to retain it and its shaft or axis from rotating at the
time the clutch has by the other end of the lever set the spur wheel thereon
free; hence it will be understood that the feed screw will remain stationery
when the dividing plate is held by the pin or stud at the one end of the lever,
and so long as the cam which acts on the other end of the lever does not
cause that end to press up the clutch so as to hold the other spur wheel fast
on its shaft or axis, whilst the screw and division plate will have motion only
when the pin or stud carried by the lever is out of the dividing plate.
In some cases in place of the means above explained for causing and

page_text: 15.
the condition (amongst others) that we, the said John Macmillan Dunlop
and Frank Crossley, our executors or administrators, by an instrument in
writing under our or their hands and seals, or under the hand and seal of
one of, us or them, should particularly describe and ascertain the nature
of the said Invention, and in what manner the same was to be per-
formed, and cause the same to be filed in the Great Seal Patent Office
within six calendar months next and immediately after the date of the said
Letters Patent.
NOW KNOW YE, that I, the said Frank Crossley, on behalf of myself
and the said John Macmillan Dunlop, do hereby declare the nature of the
said Invention, and in what manner the same is to be performed, to be par-
.ticularly described and ascertained in and by the following statement thereof,
that is to say :-
03
This Invention has for its object improvements. in; machinery for cutting
india-rubber. In order to cut sheet india-rubber into thread, it is lapped
around a mandril, and mounted in a lathe with a self-acting slide rest. A
cutter moving from the circumference of the roll of india-rubber towards the
centre or mandril cuts off threads from its end. After each cut the tool is
caused to move back rapidly, and before the next cut commences it is traversed
a short distance.
'
.
According to our Invention in order to give the forward and backward
movement to the tool a rocking shaft is employed to a sliding arm on which
the tool holder is linked. The rocking shaft receives its motion by means of
two curved tails upon it, which are acted on by studs on the faces of two
wheels, one on either side of the curved tails; the studs act on the two tails
alternately so as to produce the rocking movement; the wheel which produces
the inward motion of the cutter carries several (usually six) studs, and moves
slowly, and so it gives a slow motion to the tool. The wheel which produces
the outward motion carries usually but one stud and moves rapidly, and so
gives a rapid return motion to the tool; the feed motion is according to our
Invention given by means of a cam on the axis of the last-mentioned wheel,
which acts on the lever of a clutch, and clutches for a time a spur wheel to
it which drives the feed screw. The length of time during which the clutch is
held in so as to drive the feed motion is regulated by a disc in connection with
the feed screw; this disc has notches in it at regular intervals, into which a
projection on the clutch lever drops, and when this lever is raised by the cam
it cannot return until the feed screw has travelled so far as to enable it to fall
into the next notch on the divided plate or disc; or in place of this arrange-
ment we according to our Invention mount on the axis of the feed screw a

page_text: star wheel, and on the axis which in the former arrangement carried the cam
and clutch we mount, a locking disc and pin for locking and driving the
screw alternately..
And. in order that our said Invention may be most fully understood and
readily carried into effect we will proceed to describe the Drawings hereunto
annexed.
DESCRIPTION OF THE DRAWINGS.
.
Figure 1 is a plan, partly in section, of a portion of a self-acting lathe for
cutting india-rubber thread constructed according to our Invention; Figure 2
is a transverse section of the same taken at the lines 1, 1, Figure 1; Figure 3
is a front view, partly in section, of the same.
a, a, is the bed of the lathe, having at one end a poppet head and spindle
with belt pulleys upon it, and at the other a back centre as is usual;
between these a mandril is supported and rotated, and sheet india-rubber is
lapped upon the mandril; b, b, is a separate bed for the slide rest, it is carried
by arms b', b, bolted to it and clamped to the bed a, and which are also further
supported by pillars under their outer ends; c is a saddle or slide capable of
being traversed from end to end of the bed b by means of the screw d working
with a nut on the saddle or slide; the screw d receives an intermittent motion
by means herein-after set forth. On the top of the saddle or slide are hori-
zontal guides at right angles to the bed in which a tool holder c' is able to
slide, and to this tool holder a chisel-shaped cutter is clamped; the tool holder
is caused to move slowly inwards, so that the tool may cut off a thread from
the sheet of india-rubber on the mandril, and then to draw back rapidly to
prepare for another cut by the following means It is connected by the link e
to the lever fat à greater or less distance from the centre according to the
length of stroke reqnired; this lever f is mounted on the axis g with a groove
and feather in such manner that although it is free to slide lengthwise upon
the. axis it is compelled to rock with it; the axis has at its end curved
arms or tails g', which are acted upon by the studs h', h¹, and i' on the wheels
h and i; there are in the Drawing six pins h¹, and each of them as it passes
slowly moves the cutter forward, and in doing so cuts off a thread from the
roll of india-rubber sheet; the wheel i revolves six times as fast as the wheel h,
and the pin each time that a cut is completed causes the rapid return of
the cutting tool; the wheels h, and i both take their motion from worms on
the axis k as is shown; this axis has at its end a worm wheel k¹ gearing with a
worm on the axis 1, which axis also has belt pulleys upon it, and it is
driven by the shafting of the workshop.

page_text: -
1.
In order to obtain the feed motion, that is to say, to cause the saddle slide c
to move forward a short distance, between each cut there is clamped on the
end of the screw d a spur wheel gearing with a wheel which is on the
same axis with the worm wheel i; it is, however, mounted loosely thereon.
and has one part or cone of a friction clutch formed upon it, as is clearly
shown in Figure 3. The other part or cone m of the friction clutch, slides
on the axis with a groove and feather. At the time when the feed is
required the two parts of the friction clutch are pressed towards each other by
the lever n which rests against the part or cone m, and then the wheel i
drives the wheel and the screw d; an end view of these parts is shown at
Figure 4. The action of the lever n results from a pressure applied to.it
once in each revolution of the axis by a face cam fixed upon this axis:
this cam causes the lever to rock on its fulcrum n¹, and at the same time that
it jams the two parts of the friction clutch together it lifts a stop n on the
hinder limb of the lever out of one of the notches in the divided. plate d
which is clamped on the end of the screw d. The cam i' soon leaves the front
end of the lever n, but it is caused still to hold the parts of the friction clutch
together by the stop n riding on the face of the divided plate d. and it is not
until the next notch in this plate comes opposite the stop ² that the feed
motion ceases, the stop falling into the notch by the action of the elastic
band spring. The size of the india-rubber thread produced may be varied
by changing the divided plate and substituting another with a different
number of notches, and the gear wheels may also be changed when required.
In order to stop the action of the machine as soon as a certain number of cuts
..has been made, so as to count the threads into lots, the axis k has another
worm upon it driving a worm wheel o, on the side of which is a cam o¹, and
this when it comes round lifts by means of its incline the roller p, which is
mounted on a stud at the end of a rod p', which passes up to a lever in con-
nection with the belt fork of the strap which passes around the pulleys 1.
The lower end of the rod p¹ is slotted at p¹, and a stud q' on the, shorter arm
of the lever q enters this slot and serves to guide the rod p' in its rise and
fall; q is the centre or fulcrum of the lever; q and r is a stop which
prevents the longer arm of the lever descending beyond the horizontal position.
To start the apparatus when it has been stopped by the cam o¹ coming round,
as already described, the longer end of the lever q is lifted by hand, and this
takes the roller p forward off the nose of the cam, it then descends by its own
weight and that of its rod, and the machine is again started. In place of
employing the mechanism herein-before described to feed the saddle slide
forward between each cut, the mechanism which is shown in side view at

page_text: Figure 5, and in front view at Figure 6, may be employed. On the axis a
discs and an arm s¹ are fixed, and the feed screw d carries a star wheel t
with a number of hollows on its periphery which fit against the disc, each as
it comes round; thus the screw is held stationary until when the cutting tool
is out of work, the arm s¹ comes up and a pin six at the end of it enters
one of the notches t¹ between the horns of the star wheel; these notches, as
will be seen, are intermediate of the curved hollows, and when the pin six
drops into one of them it turns the star wheel and screw partly round, the
discs being cut away opposite the pin sx to admit of it. The size of the
india-rubber thread produced may be varied, as desired, by changing the star
wheel disc and arm and substituting others of different sizes.
In witness whereof, I, the said Frank Crossley, have hereunto set my
hand and seal, this Fourteenth day of May, in the year of our Lord
One thousand eight hundred and sixty-seven.