Improvements in Machines for Milling Screws, Worms, and the like.
Year: 1899

page_text: PROVISIONAL SPECIFICATION.
Improvements in Machines for Milling Screws, Worms, and the like.
I, HENRY LIEBERT, of Perseverance Works, Milnrow, in the County of Lan-
caster, Engineer, do hereby declare the nature of this invention to be as follows:-
-
This invention relates to improvements in an invention for which I have
obtained Letters Patent No. 9329 of 1897, and the object of my present invention
is, firstly, to provide means whereby long lengths of screws or worms can be
milled in a short machine; secondly, means for milling multiple threads;
thirdly, means for milling nuts or internal screws fourthly, improved means
for supporting the work whilst being milled, fifthly, means for taking the burr
of the thread milled, and lastly, automatic means for quickly raising the milling
tool out of and lowering same into the thread again without altering its position
relative to the work.
In carrying out the first part of my invention, instead of employing a solid
spindle to rotate and feed the work under the milling tool, I mount in the
respective carriage a hollow spindle or tube, furnished at its inner end with a
chuck whilst at the headstock end I employ upon the bed of the machine, a
bracket adapted to grip the work.
The said gripping bracket is formed preferably with a split boss adapted to
receive interchangeable bushes each having a different bore to suit the various
diameters of work.
These bushes are also split and by a screw employed in the split part of the
said boss, can be drawn tight around the work when required to hold it.
The work to be milled is placed into the said tube and secured thereto by its
chuck.
After having milled a length, the work is gripped at its furthest point by
the said gripping bracket and released by the said chuck at the opposite point,
the tube carriage then moved back to the tail end of the machine by a quick
return, the work secured again in the tube and released by the said gripping
bracket after which the operation is repeated until the whole length of work has
been milled.
In lieu of rotating the tube in which the work is secured by a train of wheels
employed at the tail end of the machine, I may form the guide screw with a
key bed and employ a train of wheels adapted to travel along with the work
carriage and rotate the work tube at the same time, or I may employ a shaft having
a key way, at the back of the machine and drive same from the guide screw by a
train of wheels at the tail end and the work tube by a train of wheels adapted
to slide with the respective carriage and rotated by the said shaft.
Referring to the second part of my invention, in order to enable of milling
multiple threads 1 employ two discs, one being rotated and the other being
secured to the said tube. In the peripheries of the said discs notches are formed
at equal distances apart from each other and in number equal to the number of
threads to be cut.

page_text: To one of the said dises is hinged a latch having a tongue adapted to engage
in the said notches so that by turning the disc on the said tube the relative position
of the said dises can be varied and the said latch being furnished with a screw
adapted to enter the respective dise, the two discs can be securely locked together.
In lieu of milling only one thread at a time, I may mill two or more simul-
taneously by employing a corresponding number of cutters formed in one out
of the solid, or formed separately but secured upon the same spindle.
Referring to the third part of my invention, nuts or internal screws may be
also milled on this machine, for which purpose I employ a special chuck secured
into the chuck on the work tube aforesaid.
This chuck is made in the form of a face plate having a shank by which it
is secured into the said work tube chuck and on its face a table rendered dia-
metrically adjustable, to which the nut or internal screw to be milled is clamped,
say by a bar and two bolts.
Referring to the fourth part of my invention, in lieu of employing in connection
with the milling tool a pedestal which incircles the work I furnish the latter with
a vertically adjustable V shaped step over which I employ a bar, the said step
being adapted to support the work and the said bar to prevent the work from
lifting out.
One end of the said bar is loosely linked onto a stud secured into the said
pedestal and rendered vertically as well as rotary adjustable, so that it may be
raised or lowered and swung to the right or left to accommodate the various sizes
and shapes of work.
The free end of the said bar is placed under the influence of a screw furnished
with a handwheel, whereby the said bar can be pressed upon the work as may
be required, the said screw being mounted in a nut rendered laterally adjustably
in an arm formed on the said pedestal so as to coincide with the position of
the said bar into which it may be swung.
Referring to the fifth part of my invention I form the said pedestal with a bed
adapted to receive a slide carrying an ordinary tool by which the threads milled
may be freed from burrs or otherwise operated upon if desirable.
Referring to the last part of my invention, in order to permit of lifting the
milling tool out of the thread and to lower same again quickly to exactly the same
depth, I employ in the neck of the bracket on which the tool bracket is adapted to
slide vertically, a bush having externally a quick thread engaging in a thread
formed in the neck of the said bracket and formed with a handle whereby the
said screw and tool bracket can be bodily lifted on the respective bracket by
giving it half a turn, the said screw being prevented from turning by a spring
lever engaging in notches formed on the hand wheel of the screw.
Dated this 29th day of May 1899.
F. BOSSHARDT & Co.,
Agents to Applicant,
I, HENRY LIEBERT, of Perseverance Works, Milnrow, in the County of Lan-
caster, 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:--
My invention relates to improvements in machines for milling screws, worms
and the like and the object is, firstly, to provide means whereby long lengths of

page_text: screws or worms can be milled in a short machine; secondly, means for milling
multiple threads; thirdly, means for milling nuts or internal screws; fourthly,
improved means for supporting the work whilst being milled; fifthly, means for
taking the burr off the thread milled; and, lastly, means for quickly raising the
milling tool out of and lowering same into the thread again without altering its
position relative to the work.
And in order that my invention may be more fully understood I have caused
to be appended hereunto one sheet of drawings marked with letters of reference
indicating like parts in the various figures.
Fig. 1 is a sectional elevation of a machine for milling screws, worms and the
like, Fig. 2 is a partial plan, and Figs. 3, 3 & 4 are end views of Fig. 1. Figs. 5
& 6 are respectively an elevation and a plan of a modification of my invention
in respect of the driving of the work tube. Figs. 7, 8, 9 & 10 are respectively
an end view, plan, front view and sectional back view of the thread milling and
cutting mechanism of the machine enlarged. Figs. 11 & 12 are respectively a
sectional elevation and end view of a special form of chuck used in connection
with my invention.
In carrying out my invention and referring to Fig. 1, instead of employing a
solid spindle to rotate and feed the work a under the milling tool b, I mount in
the work carriage ca hollow spindle or tube d supported at its outer end by the
stationary bearing and furnished at its inner end with a chuck e whilst at the
headstock end I secure to the bed f of the machine a bracket g adapted to grip
the work a.
The gripping bracket g is formed preferably with a split boss h adapted to
receive interchangeable bushes i each having a different bore to suit the var:
diameter of work, see Figs. 1 & 3.
These bushes are also split and by a bolt and nut / employed in the split part
of the said boss, can be drawn tight around the work when required to hold it as
hereinafter described.
In order to enable of milling multiple threads, Figs. 1 & 4, I employ two
discs m, n, m being rotated say from the feed screw o as shown, and n secured
to the tube d by a key p engaging in a key-way q formed along the whole length
of the said tube. In the periphery of the disc m a notch r is formed and in
that of a number of notches s at suitable distances apart from each other and
in number equal to the number of threads to be cut.
To the disc m is hinged a latch t having a tongue u adapted to engage in the
notch in the disc m and in one of the notches s of the disc n so that by turning
the disc n and the tube d, the relative position of the said discs can be varied.
The latch is also furnished with a screw v adapted to enter the disc m so that
the two discs when set as required, can be securely locked together.
In lieu of milling only one thread at a time, I may mill two or more simul-
taneously by employing a corresponding number of cutters formed in one out
of the solid, or formed separately but secured upon the same spindle as will be
readily understood.
In lieu of employing in connection with the milling tool a pedestal which
incircles the work I support the work by a √ shaped step wo clamped and rendered
vertically adjustable between two jaws, by means of a screwed bolt y and nut z
having a handle, see Figs. 7, 8, 9 & 10.
In order to prevent the work from lifting out of the said step, I employ a bar 1
over it, one end of which is loosely linked onto a stud 2 screwed vertically
adjustable into a slide 3, rendered horizontally adjustable in a pedestal 4 by
means of the bolt 5 and nut 6 having a handle, so that the said bar may be
raised or lowered and moved right or left to accommodate the various sizes and
shapes of work.
The free end of the bar 1 is placed under the influence of an eccentric 7
furnished with a handle 8 whereby the said bar can be more or less pressed upon
the work as may be required.

page_text: In lieu of the said eccentric, a weight or a screw may be used to obtain the
required pressure, the said screw being mounted in a nut rendered laterally
adjustable so as to coincide with the position of the said bar into which it may
be moved as will be readily understood, the former plan however is preferable.
In order to permit of lifting the milling tool out of the thread cut in the
work and to lower same again quickly to exactly the same depth to which it has
been set by the screw spindle 9, I employ in the neck of the bracket 10 on which
the tool bracket 11 is vertically adjustable, by the screw spindle 9, a bush 12
having externally a quick thread engaging in a thread formed in the said neck
and having a handle 13, Figs. 1 & 3.
This handle carries a spring lever 14, see Fig. 1, adapted to engage in notches 15
formed in the hand wheel 16 of the screw spindle 9, so that when giving the
handle 13 half a turn, the said bush and screw spindle turn and rise simultaneously
which causes the bracket 11 to be bodily lifted and the milling tool raised out
of the work, whilst on the return movement of the handle 13 the milling tool
is lowered again into its former position.
By depressing the spring lever 14 the screw spindle 9 is liberated from the
bush handle 13 and by means of its hand wheel 16 can then be turned at will
and the milling tool set to any desired depth.
The slide 17 which carries the V step is formed with a bed 18 upon which is
mounted longitudinally adjustable, the bed 19 furnished with the slide 20 carry-
ing the tool 21 by which the threads milled, may be freed from burrs or otherwise
operated upon if required.
The said tool may be of the ordinary kind used for cutting threads, as shown in
Figs. 2 & 3, or it may be circular as shown in Figs. 7, 8 & 9, or I may use a rotary
cutter where no great accuracy is required. The screw 22 by which the slide 20
and its tool 21 is set relative to its work, I also mount in an externally threaded
bush 23 having a handle 24 and carrying a spring lever 25 engaging in the hand
wheel 22 of the screw 22, for the purpose of quickly withdrawing and setting the
tool 21 again to its former position, as previously described in respect of the
milling tool.
When using more than one milling tool 6 an equal number of finishing tools 21
may also be employed side by side.
The screw and the like milling machine described works as follows:-
The work a to be screw threaded is in such a manner secured into the hollow
spindled by the chuck e, that it projects from the latter sufficiently to be gripped
by the bracket g, after the carriage c has arrived in the position shown in Fig. 1.
As the spindle d and the work secured thereto are rotated and fed forward
together the milling tool first cuts the thread into the work, after which the
tool 21 immediately enters and finishes the thread so that the two operations are
practically performed simultaneously. After having milled a length such as
shown in Fig. 1, the work is gripped at its furthest point by the gripping bracket
and released by the chuck e at the opposite point, the tube carriage e then moved
back to the tail of the machine by a quick return, say such as shown in Fig. 1,
the work secured again in the tube, and released by the said gripping bracket g
after which the operation is repeated until the whole length of the work has been
milled.
In lieu of rotating the tube in which the work is secured by a train of wheels
employed at the tail end of the machine, I may form the guide screw o with a
key bed 26, see Fig. 5, and employ a train of wheels adapted to travel along with
the work carriage c and rotate the work tube at the same time; or I may employ
a shaft 27 having a key-way 28, at the back of the machine, see Fig. 6, and drive
same from the guide screw by a train of wheels at the tail end, and the work
tube d by a train of wheels adapted to slide with the work carriage e and rotated
by the said shaft.
In order to permit of milling threads on objects such as studs having shoulders,
in such a manner, that the thread can be milled right up to the shoulder, I have

page_text: modified the form of work support as shown in Figs. 7, 8, 9 & 10, i.e.
form the
upper end of the V step c in two parts so as to be able of reducing the length
thereof and thus allow of feeding the stud with its shoulder right up against the
milling tool.
One of the said parts forms an arm 29, one end of which is hinged to an arm 30
formed on the V step w and the other supported by a sliding bolt 31 retained in
its normal position by a lever 32 controlled by a spring catch 33.
The upper end of the lever 32 projects in front of the stud or work a so that
when the end of the same comes in contact therewith, it will be pushed back and
through the action of the spring catch 33 afterwards entirely withdraw from
underneath the arm 29 which latter then drops and allows the shoulder of the
stud to feed up to the stationary part of the V step.
The bolt 31 and spring catch can be returned into their normal position by a
cam 34 bearing against the lever 32.
Nuts or internal screws may be also milled on this machine, for which purpose
I employ a special chuck, see Fig. 11 & 12, secured into the chuck on the work
tube aforesaid.
This chuck is made in the form of a face plate 35 having a shank 36 by which
it is secured onto the said work tube and on its face a table 37 rendered dia-
metrically adjustable, to which the nut or internal screw 38 to be milled is clamped,
say by a bar 39 and two bolts 40.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is:
1st. In a machine for milling screws, worms and the like, the feed carriage c
furnished with a hollow spindle d adapted to rotate therein and provided with
means for securing the work thereto, substantially as and for the purpose set
forth.
2nd. In a machine for milling screws, worms and the like, in combination with
the hollow spindle, specified in the preceding claim, two dises m & none of which
is secured thereto and the other rotated loosely thereon and means for coupling
together and varying the relative position of the said discs, all substantially as
and for the purpose set forth.
3rd. In a machine for milling screws, worms and the like, the work support
furnished with a vertically adjustable V step adapted to support the work, in
combination with a bar 1 rendered vertically and horizontally adjustable and
adapted to press upon and hold the work in the said step, all substantially as
set forth.
4th. In a machine for milling screws, worms and the like, the screwed spindle 9
mounted in a bush 12 which is adapted to turn and rise simultaneously in the
bracket 10 carrying the milling tool bracket 11 and means for locking the said
spindle and bush together, all substantially as and for the purpose set forth.
5th. In a machine for milling screws, worms and the like, the rotary cutter b
in combination with a second tool 21 adapted to simultaneously operate upon the
work, the former being adapted to mill the thread into the work and the latter
to finish the thread, substantially as and for the purpose set forth.
Dated this 4th day of December 1899.
F. BOSSHARDT & Co..
4. Corporation Street, Manchester,
Agents to Applicant,