IMPROVEMENTS IN LATHES, DRILLING AND BORING MACHINES
Year: 1878

page_text: PROVISIONAL SPECIFICATION left by Alexander Melville Clark at the Office
of the Commissioners of Patents on the 14th June 1878. A communication
from abroad by Fénélon Havequez-Grare, of Paris, France.
ALEXANDER MELVILLE CLARK, of Chancery Lane, in the County of Mid-
dlesex, Patent Agent. "IMPROVEMENTS IN LATHES, DRILLING AND BORING
MACHINES," [A communication from abroad by Fénélon Havequez-Grare, of
Paris, France.]
This Invention relates to improvements in machine tools, such as lathes, screw-
cutting lathes, drilling and boring machines, and consists,
1st. In the application to lathes generally for turning cylindrical work, such as
shafts or spindles, of annular cutters of novel construction, producing with greater
rapidity better work than the cutting tools usually employed.
2ndly. In a special arrangement of multiple machine for turning, boring, or
drilling, and screw cutting, either cylindrical or conical work, separately or simul-
taneously.
3rd. In the method of fixing the annular cutters, whereby they may be readily
removed, and be replaced by boring or drilling tools, in order to convert the machine
from a lathe to a boring machine, or vice versa, and whereby in a multiple machine
different pieces of work may be turned or bored at the same time.
In order that the Invention may be more readily understood, I have in the
accompanying Drawings illustrated one example of a multiple lathe capable of
turning 6 shafts or similar work at once, or of boring or drilling four pieces simul-
taneously.
Figures 1 and 2 show a longitudinal elevation and plan of the lathe as arranged
for turning shafts and other cylindrical forms with the improved annular cutting
tools.
Figures 3 and 4 show a longitudinal elevation and plan of the lathe as arranged
for turning conical forms.
Figures 5 and 6 show front and side views of the same as a multiple screw-cutting
lathe.

page_text: Figures 7 and 8 show front and side views of the same as a boring machine.
Figure 9 is an end view of the machine complete.
Figures 10 and 11 respectively show a part sectional elevation and face view on
a larger scale of the annular cutters.
The same letters of reference indicate the same parts in all these Figures.
A is the bed; B, the slide rest saddle; and C,the leading screw, all as usual;
D, head stock secured to driving end of lathe bed; E, mandrel turning in D; F,
driving cone loose on E, but capable of being made fast by a set screw in a plate G
keyed on E; a, b, c, d, e, f, gear through which the leading screw C is driven from
On an
E; g, pinion turning with driving cone F; h, spur wheel keyed on E.
eccentric prolongation of a spindle are mounted loose a change wheel and
pinion i, j, cast together, so that by giving a half turn to the shaft k they may be
made to gear with g, h, in order to vary the speed. If i, j, be in gear with g, h, as
shown, and the cone F be loose on E, the latter will be driven at the lower speed
through g, i, j, h, &c., but by turning k so as to throw i, j, out of gear, and making
the cone F fast on E the latter will be driven direct at the higher speed; l' is a
spur pinion keyed on the end of E, and provided with notches to receive the driver
and carrier m by which the work H' is carried round. This pinion drives cor-
responding pinions 11, 12, 13, 14, 15, 16, by which the different shafts or other work
H2, H3, H4, H³, He, are rotated.
For turning shafts and other cylindrical forms annular cutters I, Figures 10 and
11, are employed, each made of one piece of steel, square in form externally, and
bored slightly conical internally of a diameter corresponding to that of the work to
be turned. At the back is a shoulder by which the cutter is centred, this shoulder
entering a corresponding socket bored in the slide rest J.
The cutting edges consist of a ring of oblique teeth, as shown, and the cutters are
fixed by bolts at the four corners to the slide rest J, connected to the saddle B by
bolts in transverse slots in the latter, the two being traversed together by the
leading screw C. These cutters may be readily sharpened, and in order to avoid
undue wear they may be preceded by ordinary roughing tools n', n³, n³, n², nº, nº,
mounted in tool holders o¹, 02, 03, 0%, 0, 0, fitted adjustably in dovetail slides in
the slide rest J. The base of the slide rest has raised edges to collect the lubricant
drippings from the annular cutters.
It is only necessary to unscrew their bolta to remove the annular cutters, and
substitute mandrels or boring bars.
The turning of conical forms is illustrated in Figures 3 and 4. The shifting
head stock K is capable of being shifted transversely on a saddle L by means of a
screw ? to regulate the degree of conicality to be given to the work. Ordinary
tools n', ns, n³, n, no, no, mounted in their holders o', 0, 0, 0, 0, 0, are used.
If the work P1, P2, P3, P4, is of too large a diameter to pass through the annular
cutter sockets in the slide rest J, the work is mounted in front thereof, and the tool
holders o¹, 0, 0, 0, are mounted in brackets or castings M¹, M³, bolted to J.
To turn double conical forms, muff couplings for shafting, &c., one side is turned
first, and the work is then changed end for end.
Figures 5 and 6 illustrate the operation of cutting screws. To cut several screws
at a time the feed screws of the tool holders o¹, o², 05, 0º, are geared together by
wheels q¹, 9, 9, 98, keyed thereon, and gearing with intermediate wheels q³, q',
keyed on a common spindle. By turning the latter by means of a winch handle
applied to its squared end the whole of the feeding screws may be operated simul-
taneously to give the depth of cut required..
In order to rapidly disengage all the tools at once, and independently of the gear
by which the depth of cut is regulated each time the operation is to be recom-
menced, the nuts of their feed screws have a certain amount of play in the slide
rest J, and are connected in pairs by cross heads N1, N2, through which passes a
right and left-handed screw O provided with a handle r. By giving this screw a

page_text: This
quarter turn all the tools are immediately drawn back from the work.
screw shaft O is tubular, and the spindle of the intermediate wheels q³, q*, passes
through it.
If it is desired to cut all the screws either right or left handed a single inter-
mediate wheels, Figure 5, must be substituted for the gear wheels 13, 1, Figures 1
and 2.
Figures 7 and 8 illustrate the operation of boring. The work Q¹, Q, Q³, Q', is
centred and fixed by means of the two pairs of jaws t¹, t2, t³, t, which are slid in
guides on the slide rest J by means of the adjusting screw u having right and left
handed threads for each pair of jaws.
The work having been temporarily fixed on the boring bars v¹, v², v³, vs, by
means of the double V shaped brackets or frames R1, R2, R³, R4, connected together
by bolts x1, x2, x³, the jaws t¹, to, t³, t, are tightened up, and the work is secured.
The cutters y are followed by ordinary circular cutters 21, 22, 23, *, for the purpose
of rendering the boring more uniform and smoother.