Improvements in Screw-making Machines, also Applicable for Making Nuts and other Articles.
Year: 1889

page_text: Date of Application, 28th Mar., 1889
Complete Specification Left, 30th Dec., 1889-Accepted, 22nd Mar., 1890
Improvements in Screw-making Machines, also Applicable for Making
Nuts and other Articles.
I, WILLIAM HILLMAN of The Auto-Machinery Company, Read Street, Coventry,
in the County of Warwick, Engineer, do hereby declare the nature of this invention
to be as follows:-
The invention has for its object improvements in machinery or apparatus for making
screws, nuts and other articles automatically.
For this purpose I employ a machine fitted with a back or driving. shaft, an inter-
mediate or cam shaft, and a front or feed screw shaft, all parallel, with each other and
with the bed. The bed is fitted with a travelling head stock, the spindle of which is
bored longitudinally to permit of the passage therethrough of the rod or wire from
which the screws or other articles are to be made, and such headstock is provided with
means for firmly holding the blank rod or wire centrally. thereof. The headstock has
connected thereto a frame through bearings, in which the cam and driving shafts
freely pass, and within this frame on the driving shaft, are mounted two pulleys,
from which straps or chains pass to two pulleys on the head stock, one of such straps
being crossed, or when employing chains an intermediate wheel being employed in
the place of the crossed strap. Within the headstock frame, on the cam shaft, is
mounted a cam which, at the required times, acts on a lever-operating a clutch, so as
to reverse the rotary motion of the headstock spindle and wire or rod held therein.
The headstock is moved along the bed by the feed screw shaft, aud motion is. com-
municated from the driving shaft to the cam shaft by suitable gearing, whilst motion.
is communicated from said cam shaft to the feed screw shaft by a segmental toothed
wheel acting upon a pinion fixed on the feed screw shaft so as to give rotary motion
to the latter, and consequently a forward motion to the headstock at the required
times.
of
A slide rest is fixed on the bed at the required place, and this rest carries two tool
holding slides, which are connected by links to the outer ends of the short arms of-a-
T lever, which is mounted on an axis of motion carried by the slide rest, the long arm
such T lever being acted upon by a cam on the cam shaft to cause the slides, at the
required times, to approach each other for the purpose of cutting off the screw or other
article from the rod or wire.
A capstan "tool holder is also mounted in bearings carried by a slide mounted on
the bed with capability of a short to and fro motion thereon, which is given thereto
by a cam on a cross shaft receiving motion by bevel gearing from the main cam
shaft.
This "capstan tool holder is mounted on a horizontal axis, and receives a step by
step rotary motion by means of a ratchet wheel fixed thereon, which is operated by a
capstan "is
driver connected to a lever worked by a cam on the cam shaft. The
thus partially rotated at the required times, and it is held fast in each position by a stop
entering holes therein, such stop being suitably guided and connected to a lever worked
by a cam on the cam shaft: A saw for cutting the nicks in screw heads is fixed to a
spindle supported in bearings carried by a lever mounted on the driving shaft, and
such saw receives rotary motion by means of gearing from the driving shaft,
whilst the saw is brought into position for work and removed therefrom by a cam on
the cam shaft acting upon the lever carrying the saw spindle.
A tool for finishing the head of a screw or other article is carried by a spindle in
line with the headstock spindle, and such finishing tool is pressed up to its work

page_text: 6.
23
<
band passing
""
by spring pressure, and receives rotary motion by a strap or
round a pulley on the spindle thereof and round a pulley on the driving shaft.
The capstan tool holder, in addition to carrying the cutting and screwing or
tapping dies, also carries a gripper," which receives the shank of the screw or other
article and carries it round to the nicking and finishing tools.
This "
gripper
consists of a die, which is split for a suitable distance into three jaws. The gripping
die is formed conical on its outer surface to fit a conical recess in the carrying chuck,
which is a fixture, and the gripping die is formed with a screwed stem, around which
is placed a strong spring, which at one end acts on a shoulder in the carrying chuck,
and at the other, on a nut screwed on to the stem of the gripping die. The end of
said stem is cut half away, and it is acted upon by a fixed cam, formed or fixed on a
spindle in the centre of the hollow axle of the " capstan." The gripping die is thus,
at the required time, forced forward by the fixed cam, and is thereby opened, in which
position it receives the article as it is cut off; it remains open for a certain time until,
in the revolution of the " capstan," the said article is pressed into the die by a fixed
wiper, at which time the stein of the gripping die slips suddenly off the fixed cam, .is
closed by the spring, and thus secures a firm grip of the article with the latter properly
in position therein, and retains its hold until after the finishing operation is performed
and it has arrived at a vertical position to the underside of the capstan, at which
time the gripping die is fully opened by the fixed cam and the article released and
dropped therefrom.
The screwing or tapping die or tool is capable of endway, but not rotary, motion in.
its chuck, and it is held therein by spring pressure; the said screwing or tapping tool
is, by the cam acting upon the capstan slide, brought into contact with the article
to be screwed or tapped, and is forced only a slight distance when it stops, but the.
screwing or tapping tool having commenced its work, the spring holding it in its
chuck, gives way and allows it to be gradually drawn forward by its work, until thè
latter is completed.
The cams for effecting the step by step rotary motion of the " capstan, and for
holding the latter, are formed of discs with slots, in which suitable cam projections
are fixed, according to the work to be done.
until the blank rod ōr
and the roughing tool
I will now describe the operation of producing a plain screw with a nicked
head and the thread extending the full length of the shank up to the head..
The headstock is caused to advance towards the " capstan,
wire is carried forward the distance required; the " capstan
are then advanced, until the stem of the screw is roughly turned, the roughing tool
then retires, the " capstan is revolved, and the finishing turning tool brought into
position and advanced for finishing the turning of the shank; the "capstan" again
retires, is revolved, and again carried forward with the screwing die in position to
form the thread of the screw as before explained, the " capstan again retires, and
the cutting off operation begins, the gripping die then advances, receives the shank
of the screw and the cutting off is then completed, the " capstan again revolves,
carrying the screw past the wiper, and grips it as before explained, and continues its
motion until the screw arrives at the upper vertical position.
The capstan
"slide
is then traversed under the nicking saw, the latter is lowered into position and, in the
traverse of the screw past the same, forms the nick, the screw is then carried round
to the finishing cutter, which finishes the head, and afterwards, when it arrives at
the lower vertical position, it is released and falls into a suitable receptacle.
::
The operation of roughing the shank of one screw takes place at the same time as
the nicking of the previously cut off screw.
The number of tools carried by the " capstan and the succession of operations
effected thereby, will be regulated according to the article it is intended to
produce.
The machine is provided with a self-acting "safety stop," which is acted upon
by the sliding headstock, when the latter arrives at a given point, to stop the motion
of the cam shaft.

page_text: When the sliding headstock has travelled its full distance, it acts on the stop rod
and thereby disconnects the driving gear from the feed screw, after which the head-
stock is run back by means of a crank handle on the end of the feed screw, the
blank rod or wire is again adjusted therein, the feed screw again placed in gear and
the machine operated as before.
Improvements in Screw-making Machines, also Applicable for Making
Nuts and other Articles.
I, WILLIAM HILLMAN of The Auto-Machinery Company, Read Street, Coventry,
in the County of Warwick, 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, reference being had to the accom-
panying drawings and to the Figures and letters marked thereon:--
The invention has for its object improvements in machinery or apparatus for
making screws, nuts and other articles automatically and the invention is illustrated in
the accompanying drawings in which
Figure 1. is a front view,
Figure 2. is a plan, and
Figure 3. is a left hand end view of a machine adapted automatically to make
screws of the pattern represented at Figure 4.
Figure 5. is a right hand end view with some of the parts removed.
Figure 6. is a vertical cross section on the line 1. 1 of Figure 2.
Figure 7. is a vertical cross section on the line 2. 2 of Figure 2.
Figure 8. is a front view of the parts represented at Figure 7 and
Figure 9 is a plan thereof.
"3
Figures 10 and 11 are vertical sections of the "capstan tool holder drawn at right
angles to each other and to an enlarged scale.
Figure 12 is a cross section,
Figure 13 is a plan, and
Figure 14 is a front elevation of the slides, slide rest and parts for operating the
cutting off tools. Figure 15 is a vertical longitudinal section of the headstock
frictional driving gear.
Figure 16. is an internal view of. one of the headstock driving wheels showing the
sliding friction segments.
Figure 17. is a face view,
Figure 18. is a side view and
22
Figure 19. is a plan view of the driver and guides for the friction segments, and
Figure 20 are an elevation and edge view of the cam for operating the "capstan
stop.
Figure 21. is a cross section, and
Figure 22, is a plan of parts showing a modification in the method of communicating
motion to the travelling headstock, and in the spindle driving arrangements.
Figure 23 is a cross section, Figure 24 is a plan, and Figure 25 is a front elevation,
representing a slight modification in the method of communicating motion to the
cutting off tools, and Figures 26, 27 and 28 are respectively an elevation, a vertical
edge view, and a plan of the cams c and a² used with the modifications shown at
Figures 21 and 22.
In all the figures like parts are indicated by similar letters of reference.
In carrying my invention into effect, I employ a machine fitted with a back or
driving shaft A, an intermediate or cam shaft B, and a front or feed screw shaft C; all

page_text: parallel with each other and with the bed D. The bed D is fitted with a travelling
headstock a, the spindle a of which is bored longitudinally to permit of the passage
therethrough of the rod or wire X, from which the screws or other articles are to be
made, and such headstock a is provided with a set screw a² for holding the blank rod
or wire therein. The headstock a has connected thereto a frame a³ through bearings,
in which the driving shaft A and cam shaft B freely pass, and within this frame, on
the driving shaft, are mounted two pulleys b. b₁, from which straps or chains c. c¹ pass
to two pulleys d. d' on the headstock spindle a one of such straps being crossed, or
when employing chains as the driving means an intermediate wheel being employed
in the place of the crossed strap.
Within the headstock frame a³ on the cam shaft B is mounted a came which at
the required times acts on a lever e¹ operating a clutch e to move it in one or the
other direction to reverse the rotary motion of the headstock spindle and wire or
rod X held therein.
The mode in which this is preferably effected is as follows:-Within each of the
pulleys are two sliding frictional segments & shaped to fit the interior of the
rims of the said pulleys and fitted to slide in guides formed in drivers d fixed to
the head-stock spindle a¹. These drivers are provided with lugs do to which are pin
jointed levers do which pass through the spaces between the webs of the segments
and the headstock spindle a¹ and extend through holes d in the drivers a short
distance beyond the pulleys d. d in position for their outer ends to be acted upon by
one or other of the cam surfaces or circular inclines e formed at the ends of the
sleeve of the sliding clutch e². By these means when the cam c acts to throw the
sliding clutch towards one or the other of the pulleys d d', the levers do of that pulley
are caused to push the frictional segments & forcibly against the rim of said pulley
and thereby connect said pulley with the adjacent driver d which will drive the
headstock spindle a in a certain direction, the reverse motion of the sliding clutch ²
throwing the opposite pulley d or d into connection with the headstock spindle a¹ and
therefore driving it in the contrary direction.
The headstock a is moved along the bed D by the feed screw shaft C and motion is
communicated from the driving shaft A to the cam shaft B by suitable gearing, that
represented in the drawing being arranged as follows. On the driving shaft A is
fixed a chain wheel f which by a chain f¹ communicates motion to the chain wheel g
mounted loosely on the cam shaft B and which by a toothed pinion g' fixed thereto
communicates motion to the toothed wheel h which by a toothed pinion ¹ fixed thereto
gives motion to the toothed wheel fixed on the cam shaft B; and in order that the
motion of the cam shaft B may be capable of being instantly stopped when desired
the toothed wheel hand pinion h¹ are mounted on a stud /* fixed at the angle of
the lever 2 the short arm of which is mounted on the stud 3 whilst the long arm
thereof is acted upon by a spring to raise it and therefore to take the toothed
wheel h and pinion h¹ out of gear with the pinion g' and wheel and is held down by
the end of a rod j so as to keep the toothed wheels and pinions in gear until such
rod is moved endwise to release the L lever therefrom. Motion is communicated
from the cam shaft B to the feed screw shaft C by a segmental toothed wheel k fixed
thereon and which acts upon a toothed pinion 7 fixed on the screw shaft C so as to
give rotary motion to the latter and consequently a forward motion to the headstock a
at the required times.
A slide rest m is fixed on the bed D at the required place and this rest carries two
tool holding slides m² m², which are connected by links m² m² to the outer ends of
the short arms of a weighted T lever m³ which is mounted on an axis of motion m
carried by the slide rest m, the long arm of such T lever being acted upon by a
cam m on the cam shaft B to cause the slides m m at the required times to
approach each other for the purpose of causing the cutters m* to cut off the screw or
other article from the rod or wire X.
A "
"
capstan tool holder n is mounted on a hollow horizontal axis n¹ and
receives a step by step rotary motion by means of a ratchet wheel n² fixed thereon

page_text: which is operated by a driver n³ connected. to a sliding rod n* operated by a
weighted lever n³ worked by a cam ne on the cam shaft B.
The "
1
capstan is thus partially rotated at the required times and it is held fast
in each position by a spring stop o entering holes n* therein such stop being suitably.
guided and connected to a lever o worked by a cam of on the cam shaft B and so
arranged as to withdraw the stop from a hole n at the time when it is required
to revolve the " capstan."
A saw p for cutting the nicks in screw heads is fixed to a spindle p' supported in
bearings carried by a lever 2 mounted loosely on the driving shaft A and such
saw receives rotary motion by means of a bevelled toothed wheel p³ fixed on the
driving shaft which gives motion to the bevelled pinion p' and toothed wheel 75
which latter gives rotary motion to the toothed pinion p fixed on the saw spindle .p!.
The saw. p is brought into position for work and removed therefrom by the
combined action of a weight p² and cam p'on the cam shaft acting upon the
lever p carrying the saw spindle p¹. A tool q for finishing the head of a screw
or other article is carried by a spindle in line with the headstock spindle a¹ and
such finishing tool is pressed up to its work by spring pressure applied by a spring g'
and receives rotary motion by a strap or band 93 passing round a pulley q' on the
spindle and round a pulley 95 on the driving shaft A.
The "
capstan "tool holder'n carries a roughing turning-die or tool 'n' a finishing
turning-die or tool n³ a screwing or tapping die n and.a "gripper" no, which latter
receives the shank of the screw or other article being made and carries it round to the
nicking saw p and finishing tool g. This gripper consists of a die 10 which is split for a
suitabledistance into three jaws and is formedconical on its outer surface tofit à conical
recess in the carrying chuck n which is a fixture in the "capstan" and the gripping
die is formed with a screwed stem around which is placed a strong spring which at
one end acts on a shoulder in the carrying chuck n¹and at the other on a nut n¹³screwed
on to the stem of the gripping die n¹º. The end of said stem is cut half away and the
remaining portion is inclined on the outer side and is acted upon by a fixed cam ni
formed or fixed on a fixed spindle 15 in the centre of the hollow axle n' of the
capstan "such spindle 15 being held against rotation by an arm n¹ fixed at one
end thereof and through which a pin n is passed into the casting carrying the
capstan." The gripping die 10 is thus at the required time forced forward by the
fixed cam n and is thereby opened in which position it receives the article as it is
cut off from the rod X, it remains open for a certain time until in the revolution of the
capstan "the said article is. pressed into the die n10 by a fixed wiper r at which
time the stem of the gripping die 10 slips suddenly off the fixed cam n" and is closed
by the action of the spring n¹ thus securing a firm grip of the article with the
latter properly in position therein and it retains its hold until after the finishing
operation is performed and it has arrived at a vertical position on the underside of
the capstan" at which time the gripping die n10 is fully opened by the fixed
cam n and the article is released and dropped therefrom.
**
18
"
<<
The screwing or tapping die or tool n is capable of endway but not rotary motion
in its chuck n and it is held therein by spring pressure in the following manner.
The cylindrical body n18 of the die n³ is formed with slots n¹ in its sides and
through these slots a cross pin n is passed which is fixed in the body of the
chuck n a spiral spring n placed within the body n¹8 bears at one end against
the fixed pin 20 and at the other against the bottom of the body n18. The said
screwing or tapping tool n is by the cam no acting on the " capstan "slide n' brought
into position for acting on the article to be screwed or tapped and the "capstan" is
forced only a slight distance towards such article when it stops, but the screwing or
tapping tool or die n having commenced its work the spring n holding it in its
chuck n gives way and allows it to be gradually drawn forward by its work until
the latter is completed.
The cam n for effecting the step by step rotary motion of the "
"
capstan n and the
cam o for acting on the "capstan" stop or holder o are formed as shown of discs

page_text: with slots in which suitable cam projections are fixed according to the work to be
done.
The axle "n" of the "capstan" tool holder n is mounted in bearings formed in
a slide s mounted on the bed D and such slide s receives its necessary to and fro
motions by the combined action of a cam s¹ and spring s2, a roller 3 being mounted
on the slides to bear against the cam.
The cam s is mounted on the cross shaft to which motion is communicated from
the. cam shaft B by the bevelled toothed pinions 35, 56.
The hollow spindle a of the headstock may as stated in my provisional specifi-
cation be provided with means for firmly holding the blank rod or wire X centrally
thereof but as such rods or wires frequently slightly vary in size and it is necessary
that they should accurately fit the guide bearing carried by the cutter slide rest m
I prefer to adopt the arrangement represented in the drawings in which the hole
through the chuck or nozzle of the hollow spindle a¹ is large enough to accommodate
slight differences in size of the rod or wire and the latter is held securely therein
by the set screw a² already referred to but in order to enable such. rod or wire
accurately to fit the guide bearing t I fix to the cutter slide rest m close to such
bearing a cutter which is so adjusted as to turn the blank rod or wire X to the
exact size required to fit the bearing t.
The stop rod is provided with an adjustable arm which is acted upon by the
sliding headstock a as the latter arrives towards the limit of its motion by which means
the said rod jis caused to slide in its bearings so as to remove the left hand end
thereof from over the lever h² which latter being then free is raised by the spring h
so as to take the toothed wheels h h out of gear with the toothed wheels g¹ and
thereby stop the motion of the cam shaft B,
" tool holder n and cross-
capstan
shaft s¹.
.:
When the sliding headstock has travelled its full distance and acted upon the stop.
rod and thereby stopped the motions of the various parts as above described, the
headstock a is run back to its starting point, by means of a crank handle C¹ on
the end of the feed screw C the blank rod or wire X is again adjusted therein the
gearing again placed in gear by means of the L lever hand stop rod j and the
machine thereby placed in operation. The work can be stopped at any time by
I will now describe the
the attendant sliding the rod j to the right hand.
modifications represented at Figures 21 to 28. According to the modification of
parts represented at Figures 21 and 22 I dispense with the feed screw C and
employ in lieu thereof a toothed rack C* fixed to the bed D, toothed wheel a carried
by the headstock a, a ratchet wheel a fixed on the axis of such toothed wheel a*, and
a driver a acting upon the ratchet wheel as and operated by a cam a' on the cam
shaft the thickness of which cam is in proportion to the length of screw to be made;
by these means I am enabled readily to vary the amount of motion given to the
headstock. I also according to said modification apply the clutch e and friction
driving segments to the shaft A and pulleys b. 61 instead of to the headstock spindle a¹,
and pulleys d. d, and I arrange the cam e and lever e¹ accordingly. I also reverse
the position of the pulleys b. b and d. d' on their respective shafts and I convert the
pulleys b. d into chain wheels and give motion from one to the other by an endless
chain so as to give a positive motion to the headstock spindle when the rod or
wire X is caused to revolve against and to be acted upon by the various tools.
In the modification of parts represented at Figures 23 to 25 instead of connecting
the tool slides ml m¹ to the short arms of a single T shaped lever operated by a single
cam I connect each tool slide m¹ to the short arm of a separate L shaped lever m³
and I operate each of said levers by a separate cam m³ or m5* one of such cams (m5)
being shaped and arranged to complete the to and fro motion of its slide a little
before the other (m5) which latter acts more slowly and completes- its motion a little
later than the former at the same time causing its cutter to pass slightly beyond the
centre of the wire or rod X and thereby take off the burr which would be left if the
cutting off tools travelled exactly similarly to each other,

page_text: I will now describe the operation of producing a plain screw with a nicked head
and the thread extending the full length of the shank up to the head as represented
at Figure 4.
The blank wire or rod X is first adjusted in the hollow spindle of the headstock and
through the guide bearing t.
the
37
"
"
6i
"
"
"
The headstock with the hollow spindle revolving is caused to advance towards the
capstan until the blank rod or wire X is carried forward the distance required;
capstan and the roughing tool or die are then advanced until the stem of the
screw is roughly turned, the capstan "and the roughing tool then retire, the
capstan is revolved, and the finishing turning tool n brought into position and
advanced for finishing the turning of the shank; the " capstan" again retires, is
partially revolved and again carried forward with the screwing die n in position to
form the thread of the screw as before explained, the motion of the headstock spindle
is then reversed to unscrew the screw from the die n³, the " capstan" again retires
and the cutters m* begin the cutting off operation, the "capstan 18 again partially
rotated so as to bring the gripping die no into position, the capstan then advances
towards the partially made screw, the screwed shank of which is received within
the gripping die which has been protruded and opened for such purpose by the
fixed cam n and the cutting off operation is then completed, the "capstan' is again
partially rotated carrying the screw past the wiper which pushes the screwed shank
fully into the gripping die, the stem of the latter at the same moment slips off the
fixed cam n, and the jaws of the gripper are powerfully closed upon the screw as
before explained; the "capstan" continues its rotary motion until the screw arrives
at the upper vertical position; the " capstan slide is then traversed under the
nicking saw 2, the latter is lowered into position, and in the traverse of the screw past
the same, forms the nick in the screw head, the screw is then carried round opposite
the finishing cutter 7 by a partial rotary motion of the capstan "the said cutter q
then finishes the head after which the " capstan" again partially rotates until the
gripping die arrives at the lower vertical position when the said die is opened by
the fixed cam and the screw thereby released and allowed to fall into a suitable
receptacle.
"
"
..
"
The operation of roughing the shank of one screw takes place at the same time as
the nicking of the previously cut off screw. The number of tools carried by the
capstan and the succession of operations effected thereby will be regulated
according to the article it is intended to produce. Fast and loose pulleys A¹ A' are
mounted upon the driving shaft A to receive a belt or strap by which the machine
is driven. In order to prevent the particles of metal removed by the various tools
from getting into the screw die I apply to the " capstan," guides or guards which
direct the soapy water used so as to cause such metal particles to be carried away
from said die.
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:-
1. The improved combination and arrangement of machinery for making screws,
nuts and other articles substantially as herein shown and described.
66
2. In machinery for making screws nuts and other articles the combination with
parallel driving shaft, cam shaft screw feed shaft and bed of a travelling headstock
fitted with hollow spindle and with reversing gear, a capstan" tool holder mounted
on a horizontal axis carried by a traversing slide and acted upon by a cam and a
spring stop, a rotary nicking saw, a pair of cutting off tools, and a finishing tool all
arranged and operated substantially as herein shown and described.
3. In machinery for making screws, nuts and other articles the combination with
an intermittently sliding headstock fitted with hollow spindle and reversing gear
of a rotating and traversing "capstan "tool holder mounted on a horizontal axis and
fitted with the required cutting tools or dies and a gripping die and fixed wiper all
arranged and operated substantially as herein shown and described.

page_text: 4. In machinery for making screws, nuts and other articles the employment of a
rotating traversing "capstan "tool holder mounted on a horizontal axis and fitted
with the necessary cutting tools or dies and with a gripping die arranged and operated
substantially as herein shown and described.