Improvements in Lathes for Turning Shafts.
Year: 1887

page_text: Date of Application, 1st July, 1887
Complete Left, 3rd Apr., 1888
Complete Accepted, 18th May, 1888
Improvements in Lathes for Turning Shafts.
I, JOSEPH BARROW of the firm of Thomas Shanks and Company of the Union Iron
Works, Johnstone, in the County of Renfrew, North Britain, Engineer do hereby
declare the nature of the said invention for IMPROVEMENTS IN LATHES FOR TURNING
SHAFTS to be as follows:-
This Invention relates to improvements in lathes for turning shafts.
In turning long shafts it is customary to use a sliding stay which is either separate
from the ordinary slide rests whereby the cutting tools are carried or the slide rests
have to be removed from the saddle of the lathe and a special construction of apparatus
substituted in which the slide rests and stay are more or less self contained.
The present Invention enables the ordinary rests of a duplex lathe to be retained
and utilized for the purpose of sliding with a self contained stay, by attaching to the
front or back rest a holding piece so formed as to contain the stay and by attaching
to the other rest a similar holding piece having in itself another slide rest upon which
is fixed the tool for turning the shaft to gauge, after the rough part has passed
through the stay. The rough turning is performed by the ordinary top rests of
the lathe.
From this construction of apparatus it results that whatever the diameter of the
stay may be it can be and is firmly fixed between the back and front rests by means of
this Invention by using the screws which actuate the bottom rests upon the saddle for
that
purpose until the stay is not only rigid but concentric with the shaft to be turned,
whilst the ordinary back and front rests as well as the finishing rest are not only close
to the work but the tools therein are at the same time capable of being adjusted
without disturbing the rigidity of any of the parts, thus enabling the present
improvements to increase the accuracy and amount of work to be done.
Dated this 30th day of June 1887
J. H. JOHNSON, DAY & JOHNSON,
115, St. Vincent Street, Glasgow,
Petitioner's Agents..

page_text: Improvements in Lathes for Turning Shafts.
I, JOSEPH BARROW of the firm of Thomas Shanks & Coy. of the Union Iron
Works, Johnstone, in the County of Renfrew, North Britain, Engineer do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:
My Invention relates to improvements in lathes for turning shafts.
In turning long shafts it is customary to use a sliding stay which is either separato
from the ordinary slide rests whereby the cutting tools are carried or the slide rests
have to be removed from the saddle of tho lathe and a special construction of apparatus
substituted in which the slide rests and stays are more or less self contained.
The present Invention enables the ordinary rests of a duplex lathe to be retained
and utilized for the purpose of sliding with a self contained stay, by attaching to the
front or back rest a holding piece so formed as to contain the stay and by attaching
to the other rest a similar holding piece having self contained with it another slide
rest upon which is fixed the tools for turning the shaft to gauge, after the rough part
has passed through the stay, the rough turning being performed by the ordinary top
rests of the lathe.
From this construction of apparatus it results that whatever the diameter of the
stay may be it can be and is firmly fixed between the back and front rests by means
of my Invention by using the screws which actuate the bottom rests upon the saddle
for that purpose until the stay is not only rigid but concentric with the shaft to be
turned, whilst the ordinary back and front rests as well as the finishing rest are not
only close to the work but the tools therein are at the same time capable of being
adjusted without disturbing the rigidity of any of the parts, thus enabling the present
improvements to increase the accuracy and amount of work to be done.
In order that my Invention may be properly understood and readily carried into
effect, I have hereunto appended four explanatory sheets of drawings in the
several Figures of which corresponding parts are indicated by the same letters of
reference.
Figure 1, is an end elevation partly in section of a portion of a duplex lathe
shewing my present improvements applied thereto.
Figure 2, is a plan corresponding to Figure 1.
Figure 3, is an end elevation of the slide rest marked A, in Figures 1 and 2.
Figure 4, is an end elevation of the slide rest marked B, in Figures 1 and 2,
Figures 5 and 6, being respectively a front and end elevation of a stay constructed
and adapted for carrying out my present improvements. The slide rests A, and B,
in the annexed Figures are constructed with second, that is to say additional upper
slide rests C, for letting in the sliding tools as is usual in a duplex lathe. The holding
pieces E, as more particularly seen at Figures 1 and 2, are cast with brackets D,
which project upwards from the holding pieces E, as there shewn. The lower parts

page_text: of the pieces E, have formed on them the snugs F, and in the upper part of the
bracket screw studs G, with nuts on them are fixed as shewn in Figures 1 and 2.
Upon the studs G, clamping pieces H, are carried. The stay pieces 1, and J, shewn
at Figures 5 and 6, are placed and adjusted centrally between the slide rests A, and B,
by turning the screws of the slide rest until all the parts are brought into their proper
relative position with each other and the work to be turned and when in such position
the stays I, and J, are clamped between the slide rests A, and B, by the clamping
pieces H, being tightened by the nuts and studs G.
In Figure 2, the slide rests A, and B, together with the additional holding pieces E,
and stay J, are shewn in position relatively with the piece of shafting K, being
turned in the lathe. In the slide rests A, and B, the front and back roughing tools
are marked L, and M, respectively and the holding piece E, of the front rest is also
provided with a tool holder N, for the purpose of carrying the finishing tool O, which
is held in the slide rest by means of the pinching screw P. The screw Q, of this slide
rest is fitted at its outer end with a worm-wheel R, in which a tangent screw operated
by the band wheel S, engages and whereby it is drawn backwards and forwards so
as to adjust the tool O, in position for performing the finishing cut upon the
shaft K.
From this arrangement it will be seen that the stay pieces I, and J, are adjusted
together so that their vertical diameter corresponds with the diameter of that part of
the shaft K, which has been operated upon by the roughing tools L, and M, and as
the relative position of the stays I, and J, with the roughing tools L, and M, is
constant and as the stays I, and J, are firmly held between the slide rests A, and B,
it follows that the slide rests, stays and roughing tools all move rigidly together
along the bed of the lathe during the turning of the shaft and gives it a constant
and equable support throughout the turning operations, whilst the tool O, for
producing the finishing cut constantly follows up at the same distance and thus the
shaft being, by the improvements constituting my Invention, firmly supported at all
times any length of shaft is thus turned and finished with a smooth surface free from
markings due to vibration or jarring of the shaft which not unfrequently happens
when the stays for supporting it whilst being turned are held in the manner hitherto
in use.
It is to be understood that the lathe is provided with several sets of stays I, and J,
to suit different diameters of shafts or shafting.
Having now particularly described and ascertained the nature of my said
Invention and in what manner the same is to be performed, I declare that what
I claim is :-
The constructing of the back and front slide rests of duplex lathes with holding
pieces so formed as to contain and hold the stay rigidly with the slide rests and
upon the front of which holders a second tool holder is provided for the purpose of
containing the tool for producing the finishing cut or turning of the shaft" to guage
substantially as hereinbefore described and shewn upon the annexed sheets of
drawings.
Dated this 21st day of March 1988
"