IMPROVEMENTS IN LATHES
Year: 1875

page_text: LETTERS PATENT to William Ford Smith and Arthur Coventry, of
Gresley Iron Works, Salford, in the County of Lancaster, Engineers
PROVISIONAL SPECIFICATION_left by the said William Ford Smith.
and Arthur Coventry at the Office of the Commissioners of Patents,
with their Petition, on the 22nd November 1875.
We, WILLIAM FORD SMITH and ARTHUR COVENTRY, of Gresley Iron
Works, Salford, in the County of Lancaster, Engineers and Tool Makers,
do hereby declare the nature of the said Invention for "IMPROVEMENTS
IN LATHES," to be as follows:-
Our Invention relates to an improved construction, combination, and
arrangement of our Patent open spindle and capstan rest lathe (No. 3878,
1873), to render it suitable for turning and chasing or screwing articles
between centres, such as forged bolts and various other articles, as well
as articles from bars placed in the open spindle as hitherto, and for
other more general work; and our improvements consist in placing a

page_text: cone bush in the end of the hollow or open spindle for a centre when
articles are to be turned between centres, this cone bush being kept
in its place by a flange from the face plate when screwed upon the end
of the spindle; also in arranging an ordinary loose forcing headstock
so as to be readily applied to the lathe bed for work to be turned,
screwed, or chased between centres, and readily removed when not
required.
For sliding by self-acting mechanism our improvements consist in
employing a shaft in bearings at the back and passing the lengthway of
the bed; upon this shaft a screw is arranged to slide, being connected
with the shaft by a key or key groove in the shaft; this screw gears
with a worm wheel on a cross shaft carried in bearings in the saddle for
the capstan or other rest, and a wheel upon this shaft drives a wheel
upon another shaft in bearings in the saddle, which shaft has a pinion
that gears with a rack on the bed of the lathe. The first-named cross
shaft in the saddle is always driven, and it is connected and disconnected
with the other shaft by a screw and friction cone. The back shaft is
driven by speed pulleys or gearing from the end of the cones driving
the open spindle.
Instead of a shaft at the back of the bed a screw shaft may be placed
in front, and an half nut may be mounted on a lever having its fulcrum
in the saddle of the slide for the capstan or other rest, so that the half
nut may be brought into or out of gear with the screw shaft as required
for turning or screw cutting, this screw shaft being geared with the open
or hollow spindle by spur wheels or other mechanism.
For tightening and taking out the play in the cone bearings of the
open or hollow spindle our improvements consist in the use of two set
screws, one screwing through the pedestal or bracket for the back
bearing until its end comes against the bracket for the front bearing,
the other set screw passing through the former bracket and screwing
into the latter bracket.
For turning or screwing headed bolts between centres our Invention
consists in mounting a plate upon the face plate of the lathe, so as to
have movement diametrically to and fro on pins or screws by means of
slots, and in mounting a second plate upon the latter plate in a similar
manner, except that its diametrical movement is at right angles to the
former; this latter plate has a square or other hole to suit the shape of

page_text: the bolts to be turned and screwed or chased, and forms a driver between
the bolt and lathe spindle.
For heavy work our improvements consist in combining "back
gearing" with the open or hollow spindle and capstan rest and chasing
lathe, which gearing is somewhat similar to the back gearing of an
ordinary back geared lathe with an excentric for throwing the gearing
in and out of action with rapidity, the weight of the lever that actuates
the excentric being sufficient to hold the gearing in its two positions.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said William Ford Smith and Arthur Coventry in the
Great Seal Patent Office on the 19th May 1876.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, WILLIAM
FORD SMITH and ARTHUR COVENTRY, of Gresley Iron Works, Salford,
in the County of Lancaster, Engineers and Tool Makers, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of November, in the
year of our Lord One thousand eight hundred and seventy-five, in the
thirty-ninth year of Her reign, did, for Herself, Her heirs and suc-
cessors, give and grant unto us, the said William Ford Smith and Arthur
Coventry, Her special license that we, the said William Ford Smith
and Arthur Coventry, our executors, administrators, and assigns, or such
others as we, the said William Ford Smith and Arthur Coventry, our
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 "IM-
PROVEMENTS IN LATHES," upon the condition (amongst others) that we, the
said William Ford Smith and Arthur Coventry, our executors or admini-
strators, by an instrument in writing under our, or their, or one 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 per-
formed, and cause the same to be filed in the Great Seal Patent

page_text: Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that we, the said William Ford Smith and Arthur
Coventry, do hereby declare the nature of our said Invention, and
in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement and the
accompanying Drawings (that is to say) :-
:-
Our Invention relates to an improved construction, combination, and
arrangement of our Patent open spindle and capstan rest lathe (No. 3878,
1873), to render it suitable for turning and chasing or screwing articles
between centres, such as forged bolts and various other articles, as well
as articles from bars placed in the open spindle as hitherto, and for
other more general work; and our improvements consist in placing a
cone bush in the end of the hollow or open spindle for a centre when
articles are to be turned between centres, this cone bush being kept in
its place by a flange or shoulder from the face plate when screwed upon
the end of the spindle; also in arranging an ordinary loose forcing
headstock so as to be readily applied to the lathe bed for work to be
turned, screwed, or chased between centres and readily removed when
not required.
For sliding by self-acting mechanism, our improvements consist in
employing a shaft in bearings at the back and passing the lengthway of
the bed, upon this shaft a screw or worm is arranged to slide being
connected with the shaft by a key and key groove in the shaft; this
screw or worm gears with a worm wheel on a cross shaft carried in
bearings in the saddle for the capstan or other rest, and a wheel upon
this shaft drives a wheel upon another shaft in bearings in the saddle,
which shaft has a pinion that gears with a rack on the bed of the lathe.
The first-named cross shaft in the saddle is always driven, and it is
connected and disconnected with the other shaft by a screw and friction
cone. The back shaft is driven by speed pulleys or gearing from the
end of the cones driving the open spindle.
Instead of a shaft at the back of the bed, a screw shaft may be placed
in front and an half nut may be mounted on a lever having its fulcrum
in the saddle of the slide for the capstan or other rest, so that the half
nut may be brought into or out of gear with the screw shaft as required
for turning or screw cutting, this screw shaft being geared with the open
or hollow spindle by spur wheels or other mechanism.

page_text: For tightening and taking out the play in the cone bearings of the
open or hollow spindle, our improvements consist in the use of two set
screws, one screwing through the pedestal or bracket for the back
bearing until its end comes against the bracket for the front bearing, the
other set screw passing through the former bracket and screwing into
the latter bracket. Or the screws may be applied at the other end of
the headstock.
For turning or screwing headed bolts between centres, our Invention
consists in mounting a plate upon the face plate of the lathe, so as to
have movement diametrically to and fro on pins or screws by means of
slots, and in mounting a second plate upon the latter plate in a similar
manner, except that its diametrical movement is at right angles to the
former, this latter plate has a square or other hole to suit the shape of
the heads of the bolts to be turned and screwed or chased, and forms
driver between the bolt and lathe spindle.
"back
For heavy work, our improvements consist in combining
gearing" with the open or hollow spindle and capstan rest and chasing
lathe, which gearing is somewhat similar to the back gearing of an
ordinary back geared lathe. Forsliding long articles without centre and
which require support, we secure to a bracket on the slide carriage a slide
which can be moved by a screw at right angles to the axis of the lathe
spindle to and from the article being turned, and on this slide we secure
a stay and turning tool which is on the opposite side, and reversed to the
roughing tool on the front. There are set screws on the stay, and to
adjust the turning cutter in relation to the stay. By means of this
combined stay and turning tool combined with the roughing tool in
front, an article may be roughed out and finished by the same move-
ment of the slide carriage.
Fig. 1 is a side elevation partly in section; Fig. 2, an end elevation
from the headstock end (which is supposed to be removed), and Fig. 3
is a plan showing our improved combination and arrangement of single
geared open spindle lathe, with a back shaft made applicable for sliding,
chasing, and other uses with or without forcing headstock.
Fig. 4, a front elevation; Fig. 5, an end elevation, and Fig. 6, a
partial end elevation from the headstock end with the headstock omitted
showing our improved combination and arrangement of single geared
open spindle lathe, with a screw in front for sliding and screw cutting,

page_text: and adapted same as the lathe shown by Figs. 1, 2, and 3, either for
work to be turned between centres, or work overhanging from the end
of the lathe spindle.
Fig. 7 is a front elevation; Fig. 8, an end clevation; and Fig. 9, a
partial end elevation similar to Fig. 6, showing our improved com-
bination and arrangement of double geared open spindle lathe, with
screw in front geared for sliding or screw cutting, and adapted for work
overhanging from the end of the lathe spindle, or work to be turned or
screwed between centres. The forcing head being used in the latter
case as shown in the modifications illustrated by the Figures above
mentioned.
The other Figures of the Drawings shown detached will be referred to
in the following description of our improvements.
A, stands; a, the lathe bed; b, the open spindle of the lathe. Its
journal in front is conical and fits the conical hole in the upper bracket
c forming the headstock. The lower bracket c¹ for the back bearing of
the open spindle b, has a parallel hole through it and fits the long
bearing which is also parallel. The "speed pulleys" d are keyed upon
the back end of the spindle b,' and are further secured by a screw nut b'.
End and lateral play is prevented by the adjusting set screws shown in
Fig. 1, and by Fig. 10 the detached plan of part of the headstock. The
upper bracket is secured to the lower bracket or headstock by screw
bolts which pass through holes in the lower and slots in the upper
bracket, which slots admit of adjustment by the set screws, one of
which (c2) screws through the lower bracket (c) until its end comes
against the upper bracket (c), and the other set screw (c³) passes
through a hole in the lower bracket (c¹), and screws into the upper
bracket (c). In Fig. 1, the lathe is shown with the cone bush e in the
end of the open spindle, which is kept in its place by the flange or
shoulder of the face platef when screwed on the end of the spindle.
This cone bush is to hold the "centre" when articles are to be turned
between this centre and that in the forcing head.
Fig. 11 is a front view, and Fig. 12, a longitudinal section of the
chuck g which is three segments used in place of the cone bush when
articles passing through the hollow of the spindles are to be gripped and
turned without centres, h being the ring screwed on the end of the
spindle by turning which the grip of the segments is tightened or

page_text: slackened as required; i is a shaft at the back of the bed in bearings, as
shown. This shaft has a key groove from end to end and upon it a
worm a slides having a key, so that it is rotated by the shaft. This
worm rotates in a forked bearing j₁ from the slide carriage j, and con-
sequently the worm slides along the shaft as the slide carriage slides
along its bed. The back shaft i is driven from the speed pulleys upon
the lathe spindle by a belt between the speed pulleys d* and i*. The
back shaft i may be driven by gearing from the lathe spindle if preferred.
The worm on the back shaft gears with a worm wheel k¹ on a shaft k,
having its bearings in the slide carriage and a pinion secured at that end
of the shaft in front of the lathe (shown in peculiar dotted line in Fig. 1)
gears with a wheel rotating loose on a shaft having bearings in a part
descending from the under side of the carriage. The last named shaft
has a pinion secured to its inner end which gears with a toothed rack a¹
on the side of the lathe bed. The wheel l' has an internal cone to fit an
external cone also on the shaft l, this latter cone being connected with
the shaft by a key upon which it can slide in the lengthway of the
shaft; that end of the shaft near the cone is screwed, and a boss l²
having arms for turning it round is screwed upon it. By turning this
screw boss one way or the other the external cone can be forced tightly
into or withdrawn from the internal cone in the wheel, consequently as
the wheel is always driven the shaft can be connected or disconnected
as desired, and the carriage can be made to slide self-acting or to remain
stationary. The handle * on the end of the shaft 7 is for moving the
slide carriage by hand when the self-acting motion is disconnected;
m is the slide carrying our improved capstan rest n, and p is our Patent
chasing apparatus shown in full line in the position in which it is when
at work, and in dotted line in the position it occupies when turned back
away from its work; 9 is the water can.
In Figs. 4, 5, and 6 the lathe shown is substantially the same as that
illustrated by Figs. 1, 2, and 3, and herein-before described with the
following exceptions:-There is a screw shaft r arranged in bearings in
front of the bed, as shown. It is driven by gearing from the wheel on
the speed pulley, as shown, which gearing may be arranged for change
wheels in the ordinary manner. There is a descending part or bracket
from the carriage which carries a stud or shaft 8 upon which a lever g¹
has its fulcrum, and one end of this lever carries a partial screw nut which
when the outer end of the lever is lifted will come into gear with the

page_text: screw », but when at liberty a spring t fixed to the carriage, as shown, will
depress the end of the lever and lift the screw nut out of gear with the
screw. Upon the same descending bracket there is another stud s
which forms the fulcrum of another lever s³, which when turned vertical
brings a projection from its boss under the nut lever s¹ and holds it in
gear with the screw; but when turned horizontally it leaves the spring t
free to act upon the nut lever (¹). The carriage is moved backward
and forward by hand by a handle on a shaft having bearings in the
carriage, which shaft at its inner end has a pinion upon it that gears
with a toothed rack a¹ on the bed, as herein-before described in reference
to Figs. 1, 2, and 3.
Figs. 7, 8, and 9 illustrate a lathe similar to that shown by Figs. 4,5,
and 6, with the following exceptions:-This is a larger and heavier class
of lathe than that shown by Figs. 4, 5, and 6, and is double geared.
66
The arrangement for taking play" out of the spindle by set screws
is shown at the other end of the headstock, Fig. 13 being a detached
plan of such arrangement. To give more leverage to the handle for
moving the carriage by hand, a pinion and wheel is introduced between
the shaft * for the handle, and the shaft which carries the pinion that
gears with the toothed rack (a') on the bed.
66
Fig. 14 is an end view of a driver" for articles similar to bolts.
turned between centres, Fig. 15 being a side sectional view, showing the
head of the bolt in the driver and between centres. f is a face plate
screwed on the end of the lathe spindle. Upon the face plate a four
armed plate u is placed, and is secured to the face plate by two set
screws u¹, which pass through slots in the plate that permit of movement
in the plate diametrically across the face plate. To the four armed
plate u a boss with two arms vis secured by set screws v¹, passing
through slotted holes on the arms and screwing into the four armed
plate, the two armed plate having thus diametrical movement at right
angles to that of the four armed plate. The two armed plate has a hole
in its boss to suit the size and shape of the head of the bolt or other
article to be rotated while being turned, chased, or screwed.
Fig. 16 is an end view of the sliding stay and cutter arrangement;
and Fig. 17 is another view of the same parallel to the plane in which
the slide moves. This arrangement is for staying and turning articles
overhanging from, the end of the lathe spindle. The slide for the stay

page_text: is mounted upon a projection from the bracket x, which carries the
chasing mechanism. This bracket has slideways formed in it, wo being
screws for adjusting the wedge tightening piece for the slide y,
y, which
is moved to and fro by the handle y' and screw y³, as shown; y* is a
screw on the end of a wedge bolt in a slot in the slide for securing the
cutting or turning tool in a groove in the slide. The V at the end of
the slide y forms the stay; 2¹ is a set screw for adjusting the cutter z
to the proper depth of cut, and 2 a set screw to form an adjustable stop
for the correct position of the stay to the work. The roughing tool is
carried on the front or capstan rest and is set to cut a little in advance
of the stay which comes upon that part as left by the roughing tool,
then the reversed finishing tool z carried on the side of the stay y
follows as the carriage moves along and finishes the sliding. But if
there is a head or shoulder on the article the stay is withdrawn by the
handle before it comes against it, and the remainder of the sliding and
facing is finished by an angle tool, the capstan rest being turned to take
away the roughing tool and bring the angle tool in its place. The
combination of this stay and reversed tool with the capstan rest and
chasing apparatus is shown in Figs. 2 and 6.
We have now particularly described the nature of our Invention and
the mode of carrying it into effect, and claim as our Invention,—
Firstly. The combination and arrangement of open spindle lathes,
single or double geared, so as to be used for turning, chasing, or screw
cutting, and arranged for either operating upon work overhanging the
end of the lathe spindle or placed between centres, as herein-before
described and illustrated by Figures 1 to 9 inclusive of the Drawings.
Secondly. The combined open spindle, capstan rest, and chasing or
screwing lathes, single or double geared, arranged either for work over-
hanging the end of the lathe spindle or between centres and either
single or double geared, as herein-before described and illustrated by
Figs. 1 to 9 inclusive.
"
Thirdly. The arrangement of two set screws for taking the "play
out of the lathe spindle, as herein-before described and illustrated by
the Drawings.
Fourthly. The combination and arrangement of mechanism for self-
acting and moving the carriage by hand, as herein-before described and
shown by Figs. 1, 2, and 3 of the Drawings.

page_text: Fifthly. The combination and arrangement of mechanism for self-
acting and moving the carriage by hand, as herein-before described and
shown by Figs. 4, 5, and 6, or Figs. 7, 8, and 9 of the Drawings.
.
Sixthly. The combination of a "driver," as herein-before described and
illustrated by Figures 14 and 15 of the Drawings.
-
Seventhly. The combined stay and reversed cutter, illustrated by
Figs. 16 and 17, and its combination with a capstan rest and also with
chasing apparatus, as illustrated in Figs. 2 and 6 of the Drawings.
In witness whereof, I, the said Arthur Coventry, on my own
behalf, and on behalf of the said William Ford Smith, have
hereunto set my hand and seal, this Eighteenth day of May,
in the year of our Lord One thousand eight hundred and
seventy-six.