A New or Improved Lathe Attachment or Appliance for Making Screws.
Year: 1895

page_text: Date of Application, 16th Dec., 1895
Complete Specification Left, 14th May, 1896-Accepted, 4th July, 1896
PROVISIONAL SPECIFICATION.
A New or Improved Lathe Attachment or Appliance for Making
Screws.
I, EMILE RAVET of 20 Clerkenwell Green, London E.C., Mechanical Engineer
and Press-tool Maker, do hereby declare the nature of this invention to be as
follows:-
My invention relates to an appliance or apparatus, capable of being attached to,
and used in connection with any kind of lathe, for making screws, and as for its
object to enable a turner to manufacture screws upon his lathe notwithstanding
that such lathe may or may not be a screw cutting lathe.
For the purposes of my invention I cast or otherwise produce from iron or other
metal a suitably shaped block, which may vary in size according to the size and
other conditions of the lathe upon which it is to be used, and this I bolt or other-
wise fix upon the front or inner face of the traversing saddle of the lathe, so that
said block may travel therewith, and in the centre or thereabouts of said block
I bore or otherwise form a circular hole or aperture, and capable of fitting into
this I provide any number of circular plugs or bushes, each having a central bore
of a diameter differing from that in the others, so that one or the other of said
plugs or bushes, when fixed in position in the said block, may, by the means of
suitable set screws, be capable of receiving and holding the length of rod or wire
of which the desired screw is to be made.
The top portion of the slide rest I remove, and in its place I screw or otherwise
fix a metallic duplex or two jawed holder, for receiving and holding one or more
of the milling, cutting and other tools necessary for forming the head, shank or
other parts of the screw to be formed from the length of wire or rod or blank in
the said bush, the said holder having also two parallel projections or bars which
carry a moving or movable table, across which is placed a preferably hollow spindle,
so arranged as to hold a suitable screw plate for forming the thread upon the
blank.
Suitable levers, cams or their equivalents are provided upon the said block or
holder, by means of which one or the other of the tools employed may, in suitable
order, Le brought into position to operate upon the said rod or wire blank for use
for their respective purposes, and by this means I automatically cut and form the
said blank, and cut a thread thereon and so form screws of any desired size or
length within the limit of the traverse of the saddle of the lathe.
Dated this 16th day of December 1895.
GEO. THOS. HYDE,
1 Broad Street Buildings, Liverpool Street, London, E.C.,
Agent for the Applicant.

page_text: A New or Improved Lathe Attachment or Appliance for Making
Screws.
I, EMILE RAVET of 20 Clerkenwell Green, in the City and County of London
Mechanical Engineer and Press Tool Maker do hereby declare the nature of
this invention and in what manner the same is to be performed, to be particularly
described and ascertained in and by the following statement:-
My invention relates to an appliance or apparatus, capable of being attached to,
and used in connection with any kind of lathe, and has for its objects to enable a
turner to manufacture all kinds of screws upon his lathe, notwithstanding that such
lathe may or may not be a screw cutting lathe.
My invention consists of a suitably shaped block, cast or otherwise produced of
iron or other metal, which may vary in dimensions according to the size and other
conditions of the lathe upon which it is to be used, and this I bolt or otherwise fix
upon that side of the saddle of the lathe next the headstock (after removing from
said saddle the usual slide rest and tool holder) so that said block may travel with
the said saddle in both its lateral and longitudinal movements, and in such a
position in said block as to be in line with the mandrel of the lathe, I bore or
otherwise form a circular hole or aperture, and capable of fitting into this I provide
a number of interchangeable blocks or bushes each having a central bore of a
diameter differing from that in the others, such bore serving as a guide for the
length of rod or wire (held by a suitable self centreing or other chuck in the
mandrel) of which the desired kind of screws are to be made, the said bushes being
fixed in position by the means of suitable set screws. The said block being also
arranged to carry certain tools necessary for performing certain functions in the
making of the said screws.
Upon the upper surface of the saddle, and occupying the same or a portion of
the position previously occupied by the removed slide rest or tool holder, I bolt or
otherwise fix a metallic duplex block or holder, having two upright portions from
which extend two jaws or wings, between which the first named block is placed,
the said holder being for receiving and holding certain of the cutting, shaping,
and other tools necessary for forming the various parts of the screws to be made
from the said length of wire red or blank. The said holder has projecting
borizontally from each of its uprights a rod or fixed spindle, parallel with each
other, upon each of which is pivotally mounted a table or plate, each capable of
being thrown out of use when necessary, one of these being employed for holding
a hollow sliding tube or cylinder, which carries the plate for cutting a thread upon
the prepared portion of the rod or blank previously mentioned, while the second
table or plate may serve as a further guide for the said blank when long screws
are being made, or for holding an American chuck, when hollow screws, screw
plugs or the like are being constructed, suitable levers, guides and other appliances
are provided upon the said block and holder for manipulating and bringing into
position in convenient order, one or the other of the several tools employed as
these are used for their respective purposes in the formation of the shank, head,
and other parts of the screws being made, and by means of which I am enabled to
construct screws of any desired dimensions within the capacity of the lathe.
I may operate the longitudinal movements of the said saddle by means of the
usual toothed rack and pinion but I prefer to use a lever for this purpose as
hereinafter explained.
In order that my said invention and the manner in which I purpose carrying the

page_text: зame into effect may be fully and clearly understood, reference is heremarter maue
to the accompanying two sheets of drawings, in which
Fig. 1 Sheet 1 is a plan view of the two armed block and some of the accessories
which according to my invention are used therewith.
Fig. 2 is an end elevation of same as viewed from the top to bottom of Fig. 1,
while Fig. 3 is an end elevation viewed in the opposite direction, Fig. 4 being a
side elevation as viewed from right to left of Fig.
Figs. 5 and 6 are front and side elevations respectively of the second block or
blank guide.
Fig. 7 is an enlarged elevation of the front table or plate forming part of
Fig. 1.
Fig. 8 is an enlarged perspective view of the hollow tube or cylinder carrying
the screw cutting plate.
Fig. 9 is a perspective view of the device I prefer to employ for effecting the
longitudinal movements of the lathe saddle in lieu of the usual rack and pinion.
Fig. 10 Sheet 2 is a perspective view of a portion of the bed of an ordinary
lathe, from the saddle of which the usual tool holder and rest has been removed,
the poppet head giving place to the device Fig. 4.
Fig. 11 is a plan view of Fig. 10 with the blocks Figs. 1 and 5 in position
thereon.
Fig. 12 is a perspective enlarged view of a device forming part of my invention,
for forming hexagon, heptagon, octogan, square or other heads upon the screws as
at Figs. 13, 14, 15 and 16, when fixed in position upon Fig. 5 as illustrated by
Fig. 17.
Figs. 18 and 19 are views illustrating certain movements of the said hollow tube
or screw plate carrier, hereinafter explained.
Figs. 20, 21, 22 and 23 respectively, are views illustrating stages in the formation
of a screw, according to my invention.
Fig. 24 is a view illustrating the use of a cutting tool for forming the screw
shank, and rounding or otherwise forming the end of same in one operation.
Figs. 25 and 26 are enlarged views illustrating a device forming part of my
invention for determining the length of the screws.
Fig. 27 is an enlarged perspective view of the second table or plate forming
part of Fig. 1, illustrating its use for carrying an ordinary American chuck and
cutting tool according to my invention, in the construction of hollow screws or
screw plugs, such as illustrated by the end and side elevations Figs. 28 and 29.
I carry my invention into effect by casting or otherwise of any suitable metal a
block having a base A, and recessed or hollowed out at B, to forin two uprights C
and C, having extensions or wings a and a', these being provided with adjustable
screws bb. The portions C and C¹ are intended to carry cutting tools for
operating upon the blank red or wire of which the screws are to be made, and for
this purpose apertures such as c (Fig. 4) are formed in both C and Ci so that
suitable cutting tools may be held therein by set screws d, as hereinafter explained.
From C and C extend horizontally, a pair of rods D and D1, the latter carrying a
sleeve e to which is fixed a table or plate E, the opposite end of which is recessed
at (Figs. 3 and 7) and rests upon the rod D, whereat E is provided with a set
screw to compensate wear. The opposite rod D carries a sleeve el to which is
fixed a table or plate E', the opposite end of which is recessed at " (Fig. 3) and
rests upon the rod D' and is provided with a like screw f" for the same purpose
as the screw f, the sleeves of both plates or tables E and El permitting these to be
thrown back from their horizontal position when required, as shewn by Fig. 3.
A suitable plate F is bolted to the free ends of D and D' for preserving the
rigidity of these.
11
The plate or table E has a central hole G while the plate E' has a central
hole G, and the plate F a central hole G", all of which are truly in line with each
other and the mandrel of the lathe. The plate E carries upon its back face a
tubular projection H, the aperture through which coincides with, and forms a

page_text: continuation of the hole G, and in this a V shaped groove 9 is formed, with
which engages a like shaped projection g¹ upon the outside of a hollow rod or
spindle J, (Fig. 8) so that J while capable of sliding in and out of G and H
cannot rotate therein while o' is in the groove g.
The said hollow rod J has a
circular head J, which carries an interchangeable screw cutting plate J", held
in position by set screws 9". The plate E also carries upon its front face a
pivotted spring pawl or cam K, the free end of which when in its normal position
corresponds in shape with, and just reaches the end of the V shaped groove g upon
the face of the hole G, while upon the top edge of the plate E, and immediately
over G is a slotted plate L, held in position by a set screw.
Upon the upright. C immediately over the rod D, is a fixed and preferably
threaded stud, upon which is pivotally mounted an arm M, carrying upon its free
end an adjustable head M', the length of the arm M being such, that when
thrown over inwardly the bead M' would be immediately in line with centre of the
screw plate J", a suitable stop being provided upon C for arresting the same
when in this position. A like arm M and head M' (not shewn in position) may be
mounted upon the upright C¹ so that the head of this may also be brought into the
same central position when desired. An enlarged view of these two arms and
their heads is shewn by Figs. 25 and 26 and their functions will be hereinafter
explained.
In Fig. 10 I shew a perspective view of a portion of the bed of an ordinary lathe
from which the poppett head, and the slide rest and tool holder of the saddle has
been removed, these being unnecessary for the purposes of my invention. I thus
have left the base of the saddle O in which are dovetail or T shaped grooves h,
and the plate O' from which the tool holder and slide rest has been removed, and
upon this plate I bolt the apparatus previously described and shewn by Figs. 1, 2, 3
and 4, suitable bolt holes being formed in the base A of this corresponding with
like bolt holes in the plate Ö', this being shewn in position by the plan view
Fig. 11.
Upon the front of the saddle O), and between the jaws a and a¹ of the block A,
I mount a metallic block P, (Figs. 5 and 6) the base of which carries upon its
under surface two adjustable lugs j and j shaped to fit two of the grooves / in the
end of the saddle O, and by the means of these and suitable nuts the said block
is held in position upon O. The block P has a circular hole or aperture capable
of receiving one of a number of bushes Q, each having a central bore of a diameter
differing from that in the others, and one of these having a bore of the required
size, is held in position in P, by the means of a set screw or its equivalent k. The
said block P is preferably shaped as shewn at Fig. 5, and to the highest part of
this is pivotally mounted a lever R, in which a slot is provided for the reception
of a suitable milling or other tool R', the functions of which will be hereinafter
explained. The position of the block P upon the saddle will be understood by
reference to Fig. 11.
The lateral movements of the saddle plate O' would be effected by the screw S
in the usual way, while the longitudinal movements of the saddle O may in some
cases where desired, be operated by the usual rack and pinion but the latter is not
shewn in Figs. 10 and 11, as I prefer in lieu of those to mount upon the end of the
saddle O, a transverse plate T, held in position by the means of suitable bolts m
engaging with certain of the grooves h, and to the centre of this is pivotally
connected one end of an arm T, the opposite end of which is pivotally connected
to a lever T", one end of which is pivotally connected to a preferably metallic
block T, constructed to engage with, and slide upon, the bed of the lathe U, and
be held in the desired position thereon by the means of a screw or its equivalent V,
upon either or both ends of T From the foregoing and by reference to Figs. 10
and 11 it will be understood that if the lever T be moved in any degree towards
the position of this shewn by dotted line Fig. 11, or in the opposite direction, the
saddle O and the apparatus thereon would be moved a like distance along the
Jathe bed U.

page_text: In practice one end of the rod or wire W (hereinafter called the blank) of which
the screws are to be made, would be secured in the self-centreing or other suitable
chuck W of the headstock W" from which it would extend through the hole in
the bush Q, in the block P, which would serve as a guide therefor. The length of
the shank of the screw is to be determined by adjusting the head M¹ of the arm M
upon the upright C, so that this when thrown over towards the centre would, when
the saddle was moved towards the headstock, abut against the end of the blank W
as at Fig. 25, and so arrest the travel of the saddle. A suitable cutting tool X
being adjusted and fixed in position in the slot c of one of the uprights C or C'
(say C) the depth of the cut would be determined by adjusting the screw 61 on the
extension or jaw a, so that when the cutter X was fed towards the blank W by
the screw S the end of the screw b¹ would abut against the end of the block P,
and so arrest the further lateral movement of the saddle plate O', and consequently
the cutter X. The shank of the screw having been thus formed the end of the
blank would be as at Fig. 20, when the stop M' and its arm M would be thrown
outward into the position shewn by Fig. 11.
The length of the thread to be cut upon the reduced end of the blank, (Fig. 20)
would be determined by the distance the stop g₁ of the tube J was within the
tubular projection H at the time the screw plate J first made contact with the end
of the blank W and this would be regulated by the slotted plate L on the plate or
table E, that is to say, if a thread one inch in length was to be cut upon the blank,
the plate L would be so adjusted that when J_was pushed into H, until its head J'
abutted against the plate L, the stop g¹ of J would be only one inch within the
tube H, as will be presently understood. The plate L having been presumably so
adjusted as to form a thread upon the whole length of the shank Fig. 20, say as
shewn by Fig. 11, and a suitable screw plate J" having been fixed in J', the
lever T would be brought more or less into the position shewn by the dotted line
in Fig. 11, or until the screw plate J₁ had conie in contact with the end of the
revolving blank W, when J¹ would commence to cut a thread thereon, and as this
was fed onto the blank the tube J would be gradually drawn towards the blank
until its stop g' was withdrawn from H and the hole G, and was outside the plate
or table E, when J would cease to cut by reason of this rotating by and with the
blank W at each revolution of which its projection 7¹ would deflect and pass the
spring pawl K as shewn by Fig. 18, until the operator reversed the direction of
rotation of the blank W, when the stop g' would abut against the end of the pawl K
as at Fig. 19 and stop the rotation of J, with its stop y immediately in front of the
end of the groove g, and this direction of rotation of the blank W would unscrew
itself from J' and so feed J back again into H. The blank would then be as at
Fig. 21.
If the head of a screw was to have a milled edge the lever T" would again
move the saddle O forward until the head of the screw was in such position, that
by bringing down the lever R on the block P, as shewn in dotted lines in Fig. 5,
the milling tool R¹ would operate, and thus produce Fig. 22. The lever R would
then be thrown out of gear as at Fig. 5, and shewn by dotted outline in Fig. 11,
when, by the means of a suitable cutter X in C' (Fig. 11) the blank may now be
cut, thus producing a screw as at Fig. 23. Or if a rim is to be left upon the head
the cut may be made upon the line a Fig. 22. In the manufacture of short
screws such as Fig. 23 I inay employ a cutting tool as at Fig. 24, so formed as to
reduce the diameter of the blank to that required, and form a round or pointed end
upon the blank in one operation, in which case the point X of the cutter X may
be used to cut off the finished screw from the blank, such a cutter is shewn in
Fig. 11.
When the head of the screw is to be of square hexagon, heptagon or octagon
shape or other than round, I employ the device Fig. 12, which consists of a
frame 1, which I bolt upon the upper surface of the block P as at Fig. 17, and
within the frame 1 slides vertically a plate 2, this being operated by a lever 3,
pivotally connected to the plate 2, and the block P. The lower end of the plate 2:

page_text: carries a spindle 4, upon which is mounted a pair of circular cutters 5, the distance
between which is regulated by a collar 6. Upon one end of the spindle 4, is
mounted a grooved pulley 7, with which engages an elastic band or cord 8, by
means of which the spindle 4 is constantly rotated by any convenient or available
power. The said frame would be so mounted upon P that the cutters 5 were
immediately over the blank W, and presuming a hexagon head was to be formed
upon the screw, the cutters 5, would, by means of the lever 3, be brought down
upon the blank as at Fig. 13, cutting the blank where shewn by dotted lines, thus
producing Fig. 14. By the means of suitable gear the blank would now be rotated
one sixth of a revolution, when the cutters 5 would be again operated cutting
through the dotted lines in Fig. 14, thus producing Fig. 15, and if one sixth of a
revolution be again given to the blank, and the cutters again brought down the
result would be Fig. 16. These operations would of course take place before the
screw was cut off from the blank.
In Fig. 26 I illustrate the use of a second arm M upon the upright C1, this
being for conducting a second adjustment of the length of the screw to be made
when such screw has a second cross sectional diameter as shewn.
Where long screws are to be made, the holder J of the screw J¹ would not. be
limited by the use of the slotted plate L, and after the stud gl had left the tube H
as described this may be led back into H by hand and a further cut be made upon
the blank, the so threaded blank passing if necessary entirely through J, and if of
such a length, through the hole G¹ in the plate E¹, and may be through the
hole G in the plate F.
When hollow or tubular screws or plugs are to be made, such for instance as that
shewn by Figs. 28 and 29, 1 first throw out of position the plate E and its
accessories into that shewn by Fig. 3, and by dotted outline in Fig. 1, and place
the plate E¹ resting upon the rod D¹, as shewn by dotted outline in Fig. 1, and in
the bole G' of the latter I mount and fix an American chuck Y, in the jaws of
which I fix a suitable cutting tool Z (shewn by dotted outline in Fig. 27). This tool
may, by means of the lever T", be fed up to the revolving blank W either before
or after this has been reduced in diameter as at Fig. 20, after which the formation
of the screw would be the same as previously described.
From the foregoing it will be understood that I am enabled by means of my
invention and the employment of suitable and in most cases well known cutting
tools, to make screws of almost every kind, and of any desired length within the
limit of the lathe, and upon any kind of lathe whether this be a screw cutting
lathe or not, and to form on such screws any shaped head, circular or otherwise,
and with or without a milled edge as may be desired.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1st. In an improved method of and means for making screws, the construction,
use and application of the herein described apparatus and the several parts con-
stituting the same, connected, combined and operating in combination with any
kind of lathe, and suitable, cutting, milling, boring and other tools substantially as
herein described and shewn by the appended drawings.
2nd. In an improved method of and means for making screws, in combination
with any kind of lathe, the combination of a block having a base A, and uprights C
and C¹, the latter having jaws or extensions a and a', provided with adjusting
screws 6, the said portions C C¹ being provided with grooves such as c for
carrying suitable cutting tools X, and having extending rods D and D¹ carrying
movable plates or tables E and E', and fixed plate F, the said table or plate E
having a tubular extension H and hole G, with groove 9 for receiving and holding
a sliding screw plate carrier J, with means for adjusting the movements of said
carrier. With block P and lever such as R and meaus for carrying the said
block P, a bush such as Q for guiding a revolving rod or wire blank W held in the

page_text: chuck of the headstock, the whole mounted upon the saddle and saddle plate O
and O' after the slide rest and tool holder has been removed, with means in the
uprights C and C' for holding suitable cutting tools such as X, for forming the
screws from the said blank, with means for operating the movements of the said
Baddle O, substantially as herein described and shewn by the accompanying
drawings.
3rd. In combination with the device or apparatus set forth in the preceding
claim, the construction and use of a tube J, carrying a suitable screw cutting
plate J", and arranged to slide in a tubular extension H upon the plate E by the
means of a stud g and groove g with slotted plate L, and spring pawl K,
connected, combined and operating substantially as and for the purposes herein
described and shewn.
4th. In combination with the device or apparatus set forth in the preceding
claims, the construction and use of one or more arms such as M having adjustable
heads such as M³, and mounted upon the uprights C and C', substantially as and
for the purposes herein described and shewn.
5th. În combination with the device or apparatus set forth in the preceding
claims, and as a means for forming a polygonal head upon the screws made, the
use and application of a frame 1, mounted upon the block P, and carrying a
sliding plate 2, operated by a lever 3, and carrying a pair of circular cutters 5,
mounted upou
a revolving spindle 4, substantially as herein described and
shewn.
6th. In combination with the device or apparatus set forth in the preceding
claims, and as a means for hollowing out the shank of the screws so made, the
employment of an American chuck Y carrying a suitable cutting tool such as Z
and mounted upon the plate E¹ substantially as herein set forth and shewn.
7th. In combination with the device or apparatus set forth in the preceding
clainis, and as a means for operating the longitudinal movements of the saddle O, in
lieu of the usual rack and pinion, the employment of a plate such as T, fixed to
the saddle O, and connected by an arm T¹ to a lever T", pivotted upon a block T
mounted upon the bed of the lathe, and fixed in any desired position thereon by
the means of a screw or the like V, substantially as herein described and shewn by
the drawings.
... ת
1206
GEO. THOS. HYDE,
1 Broad Street Buildings, Liverpool Street, London, E.C.,
Agent for the Applicant.