IMPROVEMENTS IN MACHINERY FOR MANUFACTURING SOREW NUTS
Year: 1866

page_text: . LETTERS PATENT to Edward Hammond Bentall, of Heybridge, near.
Maldon, in the County of Essex, Agricultural Implement Maker, for
the Invention of "IMPROVEMENTS IN MACHINERY FOR MANUFACTURING
SOREW NUTS,"
Sealed the 5th February 1867, and dated the 6th November 1866.
PROVISIONAL SPECIFICATION left by the said Edward Hammond Bentall
at the Office of the Commissioners of Patents, with his Petition, on the
6th November 1866.
:
:
:. I; EDWARD HAMMOND BENTALL, of Heybridge, near Maldon, in the County
of Essex, Agricultural Implement Maker, do hereby declare the nature of the
said Invention for "IMPROVEMENTS IN MACHINERY FOR MANUFACTURING SCREW
NUTS," to be as follows:-
'This Invention relates to the use of a series of machines of novel con-
struction for facilitating themanufacture of screw nuts from bar iron without
the same being required to be heated. The first stage of the process of
manufacture is to cut up bar iron into pieces of uniform size to constitute nut.
blanks. Fornuts of ordinary thickness I use a novel construction of shearing.
machine, into which the bars, arranged side by side, are fed. At every
descent of the cutter a series of nut blanks corresponding in number to the
bars fed into the machine will be severed. For nuts having what is known as
"one and a half thickness," or any greater thickness, I prefer, however, to.
employ a kind of planing machine fitted with a series of parallel cutters which

page_text: will operate upon several bars simultaneously, and cut them into nut blanks
by being traversed over the bars and fed and kept up to their work by an
intermittent feed motion. The blanks thus formed are to be centred in any
approved way, and they are then ready to be submitted to a novel construction
of drilling machine in which the centre of the nut is bored out, the blanks
being fed into the machine by hand in rapid succession. The next operation
is to tap the nut which is effected by a machine similar in construction to the
drill.. The thread having been cut, the nut is next faced in a lathe of peculiar
construction, after which the nuts are shaped in a shaping machine, and are
finally submitted to a finishing facing operation.
The shearing machine consists mainly of a stationary and moving cutter of
sufficient length to operate upon a number of parallel bars fed to the cutters
by an intermittent motion. The moving cutter is fitted to a block which
slides in vertical guides formed by the standards of the machine. To the
upper part of this block is fitted an`antifriction roller, which receives the
pressure of a cam for working the cutter; this cam is carried by the driving
shaft, which turns in bearings in a block that couples the standards together.
Attached to the cutter block are straps which lead up to and connect with a
balance lever, which lever so soon as the pressure of the cam leaves the block
will come into action and raise the cutter block. The stationary cutter is
"set up" by means of inclined planes, which support the cutter, and are
adjustable lengthwise by means of screws. A sliding standard, operated by a
traversing screw, carries a clamp in which the bars to be cut are secured
abreast of each other; these bars when presented to the cutters are held down
on the stationary cutter by means of a rock lever, which is jointed at its upper
end to a link rod carrying bowles, between which a second cam on the driving
shaftrotates, and thereby serves to give a reciprocating motion to the link rod.
By means of its connection with the link rod the rock lever is pressed down
upon the ends of the bars, and as these ends are cut off the rock lever is raised
to allow for a repetition of the feed motion. In the act of cutting the ends of
the bars are forced down below the fixed cutter, it is necessary, therefore, to
lift them above the edge of that cutter to allow for the repetition of the feed
motion; this is effected by means of a reciprocating bar, which stands parallel
to the cutter, and is carried by rods pendent from cams on the driving shaft.
The bars being raised to their proper level, the traversing screw now comes
into action and feeds the bars forwards the requisite distance for cutting off
another line of nut blanks. Motion is transmitted to the traversing screw
from the driving shaft by any ordinary arrangement of intermittent feed
motion

page_text: 2nd Cutting Machine.-The bars to be cut are placed in a clamp, side by
side, across the bed of the machine. A horizontal sliding carriage fitted with
chisel cutters is intended to cut through the bars and sever them into nut
blanks. The cutter carriage slides on the bed of the machine, and it is
operated by a rod connected with a crank pin carried by a horizontal disc
wheel; this wheel has spur teeth on its periphery which gear into a pinion
keyed to a vertical shaft carrying a crown wheel, and receiving motion from a
pinion on the driving pulley shaft. The crank pin, which receives the con-
necting rod, carries a grooved cam for giving the feed to the cutters and for
raising them for the backward stroke. The cutters are mounted in a vertical
slide, which is operated by a vertical screw shaft working in a nut at the back
of the slide; keyed to this shaft is a feed wheel, into which two pawls or clicks
take, so as to operate it in either direction. These clicks are carried at one
end of a lever that is mounted loosely on the screw shaft, and jointed to the
opposite end of the lever that carries the clicks is a rod which extends from
the cam before mentioned; this rod is slotted to allow the upper end of the
crank pin to project through it, and at its extremity it carries a bowle which
works in the groove of the horizontal cam. As therefore the cam is carried.
round by the crank pin to which it is bolted it will through its connecting rod
vibrate the lever, and thereby cause one or other of the pawls or clicks to act
upon the feed wheel; these pawls are held in gear with the wheel by pressure
springs. One pawl is employed to give the feed, and the other to lift the
cutters after the cut is made. To attain this result it is necessary to lift the
back motion pawl out of contact with the feed wheel when the other pawl is
in operation or the up-and-down motion of the slide would be alike, which
would give no feed. The "back-lift "pawl is therefore fitted with a finger,
which as the other pawl acts is brought into contact with a fixed incline, which
lifts the pawl out of contact with the feed wheel. On the motion of the pawl
lever being reversed the feed pawl will slide over the teeth, while the back
lift pawl will drop into the teeth of the feed wheel and turn it in the opposite
direction, but to a less extent than the feed pawl, and thus a progressive
downward motion will be ensured to the cutters. In front of the tool slide a
lubricating pipe is fitted, which by means of jets discharges streams of
lubricating fluid on to the bars while being cut.
The drilling machine is provided with a set of drills arranged concentrically
around a vertical shaft which is stepped into a bed plate; to this shaft is
keyed a spur wheel for driving the drills. The drills are carried.by brackets
arranged radially around a drum keyed to a hollow shaft which is carried by
a socket in the bed plate, and which receives through it the vertical shaft

page_text: whereby it is steadied in position; keyed to the top of each drill spindle is a
spur pinion gearing into the spur wheel on the vertical shaft for the purpose
of working the drills. The brackets carrying the spindles are furnished with a
lug to receive a vertical rod which carries a table for supporting the nut
blank while being drilled; this rod is free to slide in the lug to allow of the
rising and falling of the table; at its lower end the rod is fitted with an anti-
friction bowle which bears upon a concentric fixed cam suitably shaped to
give the requisite feed motion to the nut and allow of the fall of the table to
its normal position when the nut is drilled. The table is fitted with a slotted
slide to receive the nut, and projecting from the under side of the slide is a
pin, which when the nut is drilled comes round into contact with a stationary
cam bolted to the bottom of a trough which is provided to catch the lubri-
cating material. The effect of the action of the fixed cam upon the pin of
the slide is to draw out the slide and bring its recess over an opening in the
table, when the drilled but will fall out and be guided by an inclined gutter
into any suitable receptacle. A spring connecting the slide with its table now
comes into action to carry in the slide and bring in a fresh blank under the
drill. Rotary motion is given to the hollow shaft which carries the drum and
the drills and tables by a worm (on a horizontal shaft carrying a belt pulley)
gearing into a worm wheel keyed on the lower end of the hollow shaft. A
lubricating vessel carried round by the machine is used to supply lubrication
to the drills.
In adapting this construction of machine for tapping the nuts the taps are
fitted into the drill spindles, so that they may readily be drawn out to release
the nuts, which when tapped are retained upon their stems. The rise of the
concentric cam is proportioned to the length of the screwed part of the tap
and the thickness of the nut. The tap fastened by a snap is taken out and
put in place while the machine is rotating. As the speed of the taps will be
much less than that of the drills larger pinions will be required on the drill
spindles. In order to economise space in the machine these pinions are
arranged alternately at different levels, and the central spur wheel which
drives them is made sufficiently broad to gear with the pinions thus arranged.
When making these machines on a large scale, say, with some sixty drills
or taps, it is proposed to make the drum which carries the spindles stationary,
and to effect the rise and fall of the tables by means of a rotating concentric
cam. The supply of blanks to the machine may be conveniently effected by a
boy situate in a carriage which is caused to run on a circular railway sur-
rounding the machine. The central shaft will be stepped into the fixed drum
which is to be bolted to a bed plate, and to prevent the undue enlargement of

page_text: the central spur driving wheel intermediate wheels mounted on stud axles`
carried by the bed plate may be used to transmit the motion to the pinions on
the drill spindles. The nuts having been drilled and tapped as above
explained, have next to be faced, and to effect this a novel arrangement of
lathe is employed. The headstock of the lathe carries a spindle which is
fitted at its inner end with a screw to receive the nut to be faced; this screw
is fitted into a hollow nut screwed into the spindle, which arrangement admits
of screws of various sizes being used to suit the various sizes of nuts required
to be faced. Upon the spindle is mounted loosely a collar to which a spur
wheel is keyed, and this wheel gears into another spur wheel keyed on a longi-
tudinal shaft driven constantly through bevil gearing from the main driving
shaft. On the same longitudinal shaft is mounted a second wheel which
gears into a spur wheel on a hollow shaft carried by the front bearing of the
headstock, and through this hollow shaft which has a continuous rotary
motion the spindle projects. Connected with or forming part of the loose collar
before mentioned is a clutch, and connected to the headstock is a cor,
responding fixed clutch; between these and mounted upon the spindle is a
sliding clutch which revolves with the spindle, and by sliding on a feather is-
made to engage with either clutch. When it engages with the clutch on the
collar that carries the spur wheel the spindle is driven through the connection
with the collar clutch; but when the sliding clutch engages with the fixed
clutch the rotation of the spindle is arrested. The spindle is rotated in order
that the screw at the end thereof may enter and hold the nut and rotate it
under the action of the facing tool, but when the facing is completed the
rotation of the spindle is to be arrested to allow of the removal of the nut;
this removal is effected by means of a rotating spanner which slides over a
feather on the nut of the hollow shaft; this spanner is like a sliding clutch
boss, and terminates at one side in a kind of a conical cap with a central hole
shaped to correspond to the nut under action. When the nut is faced the
spanner is advanced by a lever and caused to take into the nut, which by the
rotation of the spanner will be quickly unscrewed from the now quiescent
screw. The spanner is now drawn back by a spring provided for that purpose
and the spindle again set in motion to allow of the insertion of another nut.
In order to enable the spanner to lay hold of the nut with facility the hollow
shaft and the spindle are driven at slightly different speeds, and thus the one
will overrun the other and ensure a frequent correspondence of position
between the nut and the hole in the sparner. The cutter is carried by a
transverse slide which is mounted on a saddle that is advanced up to the
work by means of a pinion which it carries gearing into a fixed rack on the

page_text: lathe bed. Mounted on the saddle is a transverse screw for giving the
traverse to the slide; jointed to the slide is a lever which carries a threaded
jaw, and which when in gear with the screw causes the slide to move across
the machine and carry the tool past the face of the nut. A cam on the axle
of the pinion before mentioned bears up the lever to bring the jaw into
contact, and when thrown out of action the lever is free to fall, and the
traverse of the slide is immediately arrested. The axial motion of the shaft
carrying the cam and pinion is obtained from another pinion mounted on the
saddle and operated by a hand lever. The rotation of the traversing screw is
effected by a bevel pinion (carried by a bracket from the saddle) gearing into a
bevil pinion on the traversing screw; through this pinion a longitudinal shaft
passes fitted with a feather to give motion to the pinion; this shaft is driven
from a spur wheel on the outer end of the lathe spindle. All the motions for
operating this machine, so far as the attendant is concerned, are derived from
one hand lever; this lever by means of a spring catch when pushed forward
connects with the lever that serves to operate the spanner and throw off the
finished nut, and the opposite end of the spanner lever being coupled by a rod
to the lever for operating the clutch, the sliding clutch will as the spanner
advances be thrown into contact with the fixed clutch; at this time the
rotation of the spindle is arrested. When the band lever is drawn back the
sliding clutch will be thrown into contact with the other clutch, and the
spindle will be again set in rotation; the spanner will be moved back and
the spring connection will then be released by a wedge lifting the catch
out of its holdfast. The further return motion of the hand lever will now
once more advance the saddle and bring the threaded jaw into contact with
the traversing screw to repeat the action of the cutter upon a fresh nut
supplied by the attendant to the machine.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Edward Hammond Bentall in the Great Seal Patent Office
on the 6th May 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, EDWARD
HAMMOND BENTALL, of Heybridge, near Maldon, in the County of Essex,
Agricultural Implement Maker, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of November, in the year of our Lord
One thousand eight hundred and sixty-six, in the thirtieth year of Her reign

page_text: did, for Herself, Her heirs and successors, give and grant unto me, the
said Edward Hammond Bentall, Her special licence that I, the said Edward
Hammond Bentall, my executors, administrators, and assigns, or such others
as I, the said Edward Hammond Bentall, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to time and
at all times thereafter during the term therein expressed,should and lawfully
might make, use, exercise, and vend, within the United Kingdom of Great
Britain and Ireland, the Channel Islands, and Isle of Man, an Invention for
"IMPROVEMENTS IN MACHINERY FOR MANUFACTURING SCREW NUTS," upon the
condition (amongst others) that I, the said. Edward Hammond Bentall,
my executors or administrators, by an instrument in writing under my,
or their, or cne of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same was
to be performed, 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 Edward Hammond Bentall, do
hereby declare the nature of my said 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 Drawings hereunto
annexed, and to the letters and figures marked thereon (that is to say) :-
This Invention relates to the use of a series of machines of novel con-
struction for facilitating the manufacture of screw nuts from bar iron without
the same being required to be heated. The first stage of the process of
manufacture is to cut up bar iron into pieces of uniform size to constitute nut
blanks. For nuts of ordinary thickness I use a novel construction of shearing
machine into which the bars arranged side by side are fed. At every descent
of the cutter a series of nut blanks corresponding in number to the bars fed
into the machine will be severed. For nuts having what is known as "one
and a half thickness" or any greater thickness, I prefer, however, to employ a
kind of planing machine fitted with a series of parallel cutters which will
operate upon several bars simultaneously and cut them into nut blanks by
being traversed over the bars and fed and kept up to their work by an
intermittent feed motion. The blanks thus formed are to be centred in any
approved way,and they are then ready to be submitted to a novel construction
of drilling machine in which the centre of the nut is bored out, the blanks
being fed into the machine by hand in rapid succession. The next operation
is to tap the nut, which is effected by a machine similar in construction to the
drill. The thread having been cut, the nut is next faced in a lathe of

page_text: peculiar construction, after which the nuts are shaped in a shaping machine,
and are finally submitted to a finishing facing operation.
In Sheet I. of the accompanying Drawings Fig. 1 is a side elevation
and Fig. 2 is a front elevation of the shearing machine. This machine
consists mainly of a stationary cutter A and a moving cutter B of sufficient
length to operate upon a number of parallel bars C fed to the cutters by an
intermittent motion. The fixed cutter A is clamped by screws to a block A¹
which is placed between the standards D, and to facilitate the adjustment
of the cutter A to its proper height it is supported on wedge-shaped
plates A³ which themselves rest upon castings forming part of the standards
D. The wedges A2 are operated by means of screws a, a, which slide
them endwise and thereby set up the block and its cutter A as required.
When the height of the cutter is thus adjusted it is secured by means of
clamping screws a¹, a¹, and cross bars a² which make the block fast to the
standards. The moving cutter B is fitted to a block B¹ which slides in
vertical guides formed by the standards D of the machine. To the upper
part of this block is fitted an antifriction roller b which receives the pressure
of a cam B for working the cutter. The cam shaft E to which this and the
other cams to be presently referred to are keyed turns in bearings in a block
that couples the standards together, and to it is also keyed a spur wheel E¹
which gears into à pinion E² keyed to a driving shaft Es, which carries a
fly wheel and fast and loose driving pulleys, as shewn at Fig. 2. Attached to
the cutter block B¹ are straps 6', which lead up to and connect by a cross
shaft with a balance lever 63, which has its fulcrum on the top of one of the
standards. This lever, so soon as the pressure of the cam B2 leaves the
block, will come into action and raise the cutter clear of the work. F is a
travelling frame operated by a traversing screw G, and provided for carrying
a clamp C¹, in which the bars C to be cut are secured abreast of each other,
and by which they are advanced as the cutting operation proceeds. This
travelling frame or carriage is fitted with flanged running wheels f, f, as
shewn best in the partial end view Fig. 3, which wheels are supported on
rails f¹ affixed to the floor of the workshop. The carriage F is fitted with
bearings to receive the trunnions of the clamp C' which project from cheeks
forming part of the lever of the under jaw. Hinged to these cheeks is the
lever of the upper jaw, and to cause the upper or movable jaw to clamp
the rods C a hole is tapped in the lever of that jaw to receive a screw which
bears upon the lower lever. By turning this screw the tail of the lever is
raised, and the jaw is proportionately depressed and caused to bite the end
of the rods.
A shoulder on the lower lever bears against a stop on the

page_text: carriage, and it is held there by a strong coiled spring which couples the tail
of the lower lever with the lower part of the carriage. This mode of
mounting the clamp leaves it free to rock when the bars are depressed by the
descending cutter, and thus prevents the bars from being bent. The bars C
when presented to the cutters are held down on the stationary cutter by
means of a rock lever H, which has its fulcrum in brackets on the standard D,
and is jointed at its upper end to link rods H¹, H¹, which embrace the cam
shaft E. These link rods carry bowles h, h, between which cams H³, H²,
keyed on the cam shaft E rotate, and thereby serve to give a horizontal
reciprocating motion to the link rods; by means of its connection with the
link rods the rock lever H is pressed down upon the ends of the bars C, and
as these ends are cut off the rock lever is raised to allow for a repetition of
the feed motion. In the act of cutting the ends of the bars are forced down
below the fixed cutter, it is necessary, therefore, to lift them above the edge
of that cutter to allow for the repetition of the feed motion; this is effected
by means of a horizontal reciprocating slotted bar I which stands parallel
to the cutter, and is carried by a pair of link rods I' which embrace
the cam shaft E, and carry bowles e that rest upon cams 12 keyed to the
shaft E. When the bars have been raised to their proper level the traversing
screw G comes into action and feeds the bars forwards the requisite
distance for cutting off another line of nut blanks. An intermittent
feed motion is transmitted to the traversing screw from the cam shaft
in the following manner :-The end of the screw G turns freely in a bearing
provided for it at the foot of the standard D, and keyed to its inner end is a
bevil pinion g; this pinion gears into a bevil pinion g¹ keyed to a transverse
shaft g2, which has its bearings in the standard D' and in a bracket standard
D¹¹, and at the outer extremity of this shaft g¹ is keyed a spur wheel g³; an
intermediate wheel and pinion g* gear with this wheel g³, and with a spur
wheel affixed to a ratchet wheel g*; this ratchet wheel 95 is mounted on a
stud axle carried by the standard D³, and on the same stud axle swings a
radius rod go, which carries a pawl that acts upon the teeth of the ratchet
wheel. Connected with this radius rod is a rod g' pendent from a rock
lever 98, which has for its fulcrum a pin on the standard D. This rock lever
carries at its inner end a bowle, which is acted upon by the cam G' on the
cam shaft E, and by that means is caused to lift the pawl and drive round the
ratchet wheel. The axial motion of the ratchet wheel 95 will be commu-
nicated through the train of gearing to the shaft G, and thus when the bars
are brought up clear of the fixed cutter, and the moving cutter is elevated, the
'feed of the bars will take place. In order to change the rate of feed with

page_text: facility the intermediate wheel and pinion 94 are mounted on a stud axle
carried by a rocking segment plate g*, which has for its fulcrum the shaftg.
This plate is slotted to receive a clamping screw, which enters the standard,
and will hold it at any required position. In order to alter the speed of rotation
of the traversing screw it will only be necessary to change the intermediate
wheel and pinion for a wheel and pinion having a greater or less number of
teeth, and to adjust the position of the segment plate so as to bring the wheel
and pinion properly into gear. For minute adjustment of the feed the slot in
the leverg" is provided. The traversing screw G passes through a tapped tube
affixed to the carriage, and it is made of sufficient length to traverse the
carriage a distance equal to the greatest length of bar to be fed to the
cutters.
:;
The machine which I employ for cutting nut blanks of more than the usual
thickness is shewn in Sheet 11. Fig. 1 is a side elevation of the machine
Fig. 2 is a plan view, and Fig. 3 is a partial transverse section taken in the
line 1, 2, at Fig. 1. It is a modified form of planing or shaping machine
carrying a number of cutters, which are set abreast of each other, and are
intended to plough through by a series of traverse motions a number of
hexagonal or other shaped bars and reduce them to nut blanks. The bars to
be cut are shown at a, a ; they are laid side by side and secured in a clamp A,
which is made fast to the bed of the machine so as to present the bars trans-
versely to the cutters; B is the main framing of the machine, provided with
V guides to receive a horizontal sliding carriage C, which is fitted with vertical
chisel cutters c. The sliding carriage C receives its motion through a con-
necting rod C¹ from a crank pin C² carried by a rotating plate C³, which is
supported by a horizontal disc wheel D; this wheel has spur teeth on its
periphery, which gear into a pinion keyed to a short vertical shaft D¹ (Figure 3),
carrying a crown wheel and receiving motion from a pinion on the driving
pulley shaft D². The spur wheel D is mounted loosely on a hollow boss
forming part of the main framing of the machine; this boss is cast with an
excentric vertical hole in order that it may receive and support the pendent
stud axle of the plate C³. In the under face of the plate C³ a radial recess
is formed to receive a slide, which is carried by a pin d projecting from the
upper face of the disc wheel; as therefore this wheel is rotated it will by
means of the pin d carry round the plate C³, giving it at the same time a
variable axial motion; the effect of this variable motion will be that the
cutters will be advanced slowly over the work to give the cut, and be rapidly
withdrawn to take up a position for renewing the cut. Before, however,
returning the cutters to their starting position it is requisite to raise them, so

page_text: that they may clear the work at their back motion, and then to lower them so
that they may be ready to renew the cutting action; this necessitates an
excess of downward over the upward motion of the cutters, which end is
obtained in the following manner :-The crank pin C2, which receives the
connecting rod C³,carries a grooved cam E for giving the feed to the cutters c,
and for raising them for the backward stroke. The cutters are secured in a
vertical slide C, which is mounted in V guides in the front of the carriage C,
and it is operated by a vertical screw shaft E¹, and is free to turn in its bearing
on the carriage. The thread of this screw shaft works in a nut at the back of
the slide, and it will therefore raise or lower the slide with its cutters according
to the direction in which it is turned. Keyed to this shaft is a feed wheel E²,
into which two pawls or clicks e,e¹, take so as to operate it in either direction;
these clicks are carried at one end of a crank lever E³ thatismounted loosely
on the screw shaft E¹, and jointed to the other end of the lever is a rod E4
which extends from the cam E before mentioned; this rod is slotted to allow
the upper end of the crank pin C2 to project through it and retain it in the
required position, and at its extremity the rod carries a bowle which works in
the groove of the horizontal cam E; as therefore the cam is carried round by
the crank pin to which it is bolted it will through its connecting rod vibrate
the lever, and thereby cause one or other of the pawls or clicks to act upon
the feed wheel. These pawls are held in gear with the wheel by pressure
springs; one pawl is employed to give the feed and the other to lift the
cutters after the cut is made. To attain this result it is necessary to lift the
back motion pawl out of contact with the feed wheel when the other pawl is
in operation, or the up-and-down motion of the slide would be alike which
would give no feed. The "back lift" pawl e¹ is therefore fitted with a finger
or pin e², which as the other pawl acts is brought into contact with a fixed
incline e³ on the carriage, which incline lifts the pawl e¹ out of contact with
the feed wheel. On the motion of the pawl lever being reversed the feed
pawl e will slide over the teeth, while the back lift pawl will drop into the
teeth of the feed wheel and turn it in the opposite direction, but to a less
extent than the feed pawl, and thus a progressive downward motion will be
ensured to the cutters. In front of the tool slide a lubricating pipe F is fitted,
which by means of jets discharges streams of lubricating fluid on to the bars
while being cut, and the overflow is received into the trough F1, and conveyed
thence to a suitable receptacle. The blanks formed, as above described, I next
centre in any well-known or approved manner, and I then submit them to the
operation of drilling, which is effected by the use of the machine shewn in
Sheet III. Fig. 1 is a vertical section of the improved drill; Fig. 2 is a

page_text: sectional plan view taken in the line 1, 2, of Fig. 1, and Fig. 3 is a sectional
plan view taken in the line 3, 4, of the same Figure.
The machine is provided with a set of drills a, a, arranged concentrically
around a vertical shaft A, which is stepped into a bed plate B; to this shaft A
is keyed a spur wheel A¹ for driving the drills. The drills are carried by
brackets C arranged radially around a drum C¹, which is keyed to a hollow
rotating shaft C stepped in a socket in the bed plate B; this hollow shaft
receives through it the vertical shaft A, and by its means it is steadied in
position. Keyed to the top of each drill spindle is a spur pinion a¹; these
pinions gear into the spur wheel A¹ on the vertical shaft A for the purpose of
driving the drills. Below the brackets carrying the drill spindles are
brackets C³ forming guides for vertical rods c which severally carry a table c¹
for supporting the nut blank while being drilled; these rods are free to slide
vertically in the bracket guides to allow of the rising and falling of the tables
which they respectively carry; at their lower ends these rods are severally
fitted with an antifriction bowle which as the tables are carried round by
the rotating drum C³runs over a concentric.fixed cam D suitably shaped to
give the requisite feed motion to the nut and allow of the fall of the tables to
their normal position when their respective nuts have been drilled. This
ring cam is shewn detached and in plan view at Figure 4. Each table is
fitted with a slotted slide o³ to receive the nut blank, and projecting from
the under side of each slide is a pin which when the nut is drilled comes
round into contact with a stationary cam d carried by a standard d made fust
to a trough D¹ provided to catch the lubricating material, and to the bottom of
which the ring cam D is secured. The effect of the action of the fixed cam upon
the pins of the several slides as they are brought into contact therewith is to
draw out each slide and bring the enlarged end of its longitudinal slot over an
opening in the table when the drilled nut will be discharged from the slide.
The chips formed in the act of drilling will fall down a central channel in the
rod c and be discharged into the trough D¹. A spring c³ connecting the slide
with its table (so soon as the slide by the revolution of the table gets clear of
the fixed cam d) now comes into action to carry in the slide and bring a
fresh blank, which has meanwhile been supplied thereto by hand, under the
action of the drill placed immediately above it. Rotary motion is given
to the hollow shaft which carries the drum and the drills and tables from a
horizontal shaft C' carrying a belt pulley; on its inner end this shaft carries
a worm C5 which gears into a worm wheel C keyed on the lower end of the
hollow shaft C³, and thus the rods c carrying the tables are caused to move
over the ring cam D, and thereby feed up the work to the drills, as required.

page_text: The rotary motion for the drills is taken from over-head gearing which, by
driving a bevil pinion in gear with a bevil wheel A² keyed on the central shaft
A causes the rotation of that shaft and the spur wheel A1 which it carries;
as therefore the pinions a¹ on the drill spindles gear into this wheel they will
receive a rapid rotation therefrom, which will be increased by the revolution of
the pinious in the opposite direction around the wheel A¹. A lubricating
vessel carried round by the machine may be advantageously used to supply
lubrication to the drills. The nuts, as they fall from the drilling machine are
ready to be tapped or have the screw thread cut in them; this operation is
performed by the machine shewn in partial sectional elevation at Fig. 1,
Sheet IV.,which machine is, as above remarked, a modification of the drilling
machine just described. Fig. 2 is a sectional plan of the tapping machine
taken in the line 1, 2, of Fig. 1, and Fig. 3 is a sectional plan taken in the line
3,4, of the same Figure. The letters of reference used in these Figures are the
same as those in the drilling, and as the construction of the two machines is
precisely similar, with the exceptions to be presently pointed out, to describe the
tapping machine in detail would only be to repeat the explanation already given
In adapting this construction of machine for tapping the nuts the taps a
are fitted into the drill spindles, so that they may readily be drawn out to
release the nuts, which when tapped are retained upon their stems. The rise
of the concentric cam (not shewn in the Drawing) must be proportioned to
the length of the screwed part of the tap and the thickness of the nut. The
tap is fastened by a snap, as shown at Fig. 1, and it is capable of being
taken out and put in place while the machine is rotating; as however the
speed of rotation of the taps will be much less than that of the drills larger
pinions will be required on the spindles of this machine than of the drilling
machine. In order to economise space. I arrange these pinions alternately at
different levels, and make thecentral spur wheel which drives them sufficiently
broad to gear with the pinions thus arranged.
When making drilling and tapping machines on a large scale, say, with
some forty to sixty drills or taps, I propose to make the drum which carries
the spindles stationary, and to effect the rise and fall of the tables by means
of a rotating concentric cam.
An arrangement of this kind is shewn in Sheet V, where Fig. 1 is a vertical
section, and Fig. a plan view of a machine fitted with forty spindles. The
construction and arrangement of the parts being in the main like the machine
shewn in Sheets III. and IV. I have marked the corresponding parts with
similar letters of reference, and shall refer particularly only to those parts which
are modified to suit the stationary drum and the rotating concentric cam by

page_text: which the tables c¹ and their slides c² are raised and lowered. The central
shaft A is stepped into a plate A*, which is carried by a column of brickwork
or masonry built up upon the bed plate A** of the machine. To the plate A*
brackets C¹ forming substitutes for the fixed drum C¹ of the former arrange-
ment are bolted; this plate also carries stud axles a² (it being cast with
sockets for the purpose), on which stud axles intermediate wheels a³ are
loosely mounted; these wheels gear into and transmit the motion of the
central spur driving wheel A², and are intended to prevent the undue enlarge-
ment of that wheel; A³ is a wheel mounted loosely on the axle A,and carrying
on its face a ring A4, which is formed with spur teeth on both its inner and
outer periphery. The intermediate wheels a³ gear into the inner ring of teeth,
and the pinions a² on the spindles a gear into the outer ring of teeth, and thus
a rapid rotary motion is given to the drills or taps as the case may be. In
this arrangement it will be seen that the pinions a' are set at different eleva-
tions, the ring of spur teeth being made sufficiently deep to admit of the
overlapping of the pinions to gain space. An annular\-groove is made in the
bed plate A** for a concentric ring guide on the under side of the trough D¹
to slide in. The cam D which serves to raise the work to the tools is mounted
in this trough, and made adjustable in height by means of screws as shown,
and secured to the under side of the trough is a concentric annular rack D²,
into which gears a pinion D³ for rotating the trough; this pinion is mounted
on a vertical spindle, which carries at its lower end a bevil pinion D4 driven
by a bevil pinion D5 on a driving shaft. At a level below the bed plate A**
is a circular railway E on which runs a carriage on platform E' for carrying
the boy whose duty it is to feed the machine with nut blanks; this carriage is
made fast by bracket arms to the trough D³, and moves therewith. The boy,
therefore, attending the machine being supplied with nut blanks places one in
each slide as he moves round the machine, displacing in the case of the tapping
machine from time to time the nuts that have accumulated upon the stem of
the taps by releasing them from their sockets in the rotating spindles, when
the nuts will falloff by simply reversing the stems; the taps thus freed of the
tapped nuts may then be instantly replaced without interrupting the action of
the machine. As the feeding in of the nut blanks must take place when the
tables c¹are at their depressed position the carriage will be affixed to the
trough opposite the most depressed part of the cam D; the nuts having been
drilled and tapped as above explained have next to be faced, and to effect
this a novel arrangement of lathe is employed. This machine is shown in
several views in Sheet VI. Fig. 1 is a side elevation of the lathe for facing
the tapped nuts; Fig. 2 is a plan view of the same; Fig. 3 is an end elevation

page_text: cap
and Fig. 4 is a cross section shewing the arrangement of some of the driving
gear. A is the headstock of the lathe, in which is mounted a spindle B; this
spindle is fitted at its inner end with a screw b to receive the nut to be faced;
the screw 6 is carried by a hollow nut 61 screwed into the spindle B,. and it
therefore admits of being readilyre moved andreplaced by a nutcarrying ascrew
of larger or smaller diameter, or of different pitch of thread. This arrangement
is adopted to suit the various sizes of nuts required to be faced. Upon the
spindle is mounted loosely a collar which carries a spur wheel C and conical
of a friction clutch C. The wheel C gears into a spur wheel D keyed
on a longitudinal shaft D¹, driven constantly through bevil gearing from the
main driving shaft. On the same longitudinal shaft D' is mounted a second spur
wheel D2, which gears.into a spur wheel E on a hollow shaft E' carried by the
front bearing of the headstock, and in this hollow shaft which has a continuous
rotary motion the spindle B has its bearing; connected to the headstock is a.
fixed conical clutch cap Cs corresponding to that on the loose collar and
mounted upon the spindle B; between these fast and loose caps is a double
coned sliding clutch C which revolves with the spindle, and is free to slide
on a feather on the spindle, in order that it may engage with either coned
cap or stand clear of both. When it engages with the cap C¹ the spindle.
will be driven through the action of the constantly rotating wheel D, which
gears into the wheel C; the connection of this wheel with the cap C¹
will cause the 'cap C¹ to rotate, and the friction of contact between the
conical cap C and the sliding clutch will ensure the rotation of the latter,
and with it the spindle to which it is keyed. When, however, the sliding
clutch engages with the fixed conical cap C³ the rotation of the spindle B
will be immediately arrested. The spindle is rotated in order that the
screw b at the end thereof may enter the tapped hole in the nut to be
faced and rotate it under the action of the facing tools, but when the facing
is completed the rotation of the spindle is to be arrested to allow of the
removal of the nut; this removal is effected by means of a rotating
spanner which is mounted on the hollow shaft E¹ and slides over a feather
on the hollow shaft. This spanner, which is shewn at E³, is like a sliding
clutch boss, and terminates at its outer end in a kind of conical cap having a
central hole shaped to correspond to the form of the nut under operation. When
the nut is faced the spanner is advanced by a mechanical arrangement to be
presently described,and caused to take on to the nut (as shown in Fig.2), and
the rotation of the spanner being continued the nut will be quickly unscrewed
from thenow quiescent screw and discharged from the machine. The spanner
is now to be drawn back, a spring catch being provided for that purpose, and

page_text: the spindle is to be again set in motion to allow of the insertion of another
nut. In order to enable the spanner to lay hold of the nut with facility the
hollow shaft E' which receives rotary motion from the wheel D2, and the
spindle B which receives its motion as before explained from the spur wheel D
on the same shaft, are driven at slightly different speeds, and thus the one will
overrun the other and ensure a frequent correspondence of position between
the nut and the hole in the spanner.
In facing the nut I'prefer to use two cutters, a roughing and a finishing
cutter; these cutters, shewn at f, f, are fixed.in a clamp F carried by a
transverse slide F¹, which is mounted on a saddle F²; this saddle slides on V
guides formed for it on the lathe bed, and it is advanced up to the work by
means of a pinion f which it carries, gearing into a rack f affixed to the lathe
bed. Mounted on the saddle F is a transverse screw F for giving the
forward traverse to the slide F¹, and a spring F4 is provided for effecting the
return motion. Jointed to the slide is a lever F* which carries a threaded
jaw, and which when in gear with the screw causes the slide to move
across the machine and carry the tools past the face of the nut. A cam f³ on
the axle of the pinion f before mentioned bears up the lever F* when it is
required to bring the jaw into contact with the screw F, and when by the
lateral traverse of the lever it has passed out of contact with the enlarged
radius of the cam the lever will by its own weight fall, and its threaded jaw
being thereby disengaged from the screw F³ the traverse of the slide will be
immediately arrested. The.axial motion of the shaft carrying the camƒ³ and
pinion f³ is obtained from a spur wheel fe mounted on a loose stud axle
carried by a bracket pendent from the saddle F². The wheel f* is operated by
a cranked hand lever G which is keyed to the stud axle as its fulcrum. The
rotation of the traversing screw F is effected by a bevil pinion f" (carried by a
bracket from the saddle) gearing into a bevil pinion on the traversing screw;
this pinionis driven bya longitudinal shaft H which passes throughitandisfitted
with a feather to give motion to the pinion; this arrangement allows of the
traverse of the pinion with the saddle. The shaft H is driven from a spur
wheel on the outer end of the lathe spindle. All the motions for operating
this machine,so far as the attendant is concerned,are derived from the cranked
hand lever G; this lever G is jointed at its upper end to a horizontal stop
rod G¹, which slides in guides provided to receive it; this stop rod is intended
to operate on theclutch C and throw it into and out of contact with the hollow
stationary and rotating cones so as to drive the shaft B and arrest its motion
at proper times, as above described. G' is a cranked rock lever connected by
a rod G³ to the fork G' that embraces the sliding clutch G³, and imparts the

page_text: sliding motion thereto; this lever G2 is connected to a fixed point on the
framing by a spring g whose tendency is to draw the lever and its connections
into a proper position for retaining the sliding clutch in contact with the cone
cap C, or keeping it in the driving position. The rod G is provided with a
rigid stop g', which when brought into contact with the lever G2 will move it
back into the position for throwing the friction clutch out of action or into
contact with the fixed conical cap; the rotation of the shalt B is by this
means stopped immediately after the spanner E2 has come into action to throw
off the faced nut from the screw b. I have said that this spanner E³ has a
sliding motion on its hollow shaft; this is to enable it to press upon and follow
up the retreating nut and throw it off the screw; and in order that a fresh
nut may be inserted in the machine it is necessary that this spanner should
then slide back. These endway motions are produced through the rocking of
the hand lever G by the attendant in the following manner:-Mounted on a
stude which projects through a segment slot in the crank leverG²is a lever E³;
this stud e is the stem of a fork that embraces a reduced diameter of the
spanner E2; the shifting therefore of the stud to and fro gives the spanner
the required sliding motion. The lever E³ is connected by a coiled spring es
to a fixed point on the framing, and by the drag of this spring a tendency is
given to the fork through the agency of the lever E3 to press the spanner
towards the nut on the screw b; while, however, the facing operation is pro-
ceeding the spanner must be held back; this is effected by means of a pin e¹²
carried by an elastic armE'affixed to the leverE³. The pin e¹ projects through
a hole in the lever G2 which lies below the lever E³,and when inserted therein
the lever Es is locked or retained in the desired position; when, however, the
spanner is required to be advanced, which is to be done immediately before
the stoppage of the rotation of the shaft B, an incline g² on the stop rod G¹
passes under the elastic arm E4, and lifting it disengages the pin e'from the
lever G2, and allows the spring e³ to come into action and rock the lever E³,
and thereby slide the spanner towards the nut. The return of the spanner to
its former or back ward position is effected by means ofayielding spring stop g³
with which the rod G' is fitted. As the rod is moved by the attendant in the
direction of the arrow, Fig. 2, this stop g³ will strike agains! the tail of the
lever-E³, and carry it forward until the pin e'is brought over the hole in the
lever G2, when it will again drop therein,and the spanner will thus be retained
in its backward position. The return or back motion of the hand lever G to
shift the clutchC³out of action,as explained above, besides doing this advances
the saddle by throwing into action the gearing f and fa, and bringing the
threaded jaw of the lever F again into gear with the traversing screw; the

page_text: action of the cutters uponafresh nut supplied bythe attendant on themachine
will then be repeated.
. Having now set forth the nature of my Invention of "Improvements in
Machinery for Manufacturing Screw Nuts," I claim,—
First, the arrangements of machinery, above described, for cutting up bar
iron to form nut blanks.
Secondly, the arrangements of machinery, above described, for facilitating
the drilling and tapping of the nut blanks.
And, thirdly, the arrangement of lathe, above described, for facing screw
nuts.
In witness whereof, I, the said Edward Hammond Bentall, have
hereunto set my hand and seal, the Fourth day of May, in the year
of our Lord One thousand eight hundred and sixty-seven.
E. H. BENTALL. (L.S.)