Improvements in or connected with Turning Lathes.
Year: 1893

page_text: Date of Application; 17th Jan., 1893
Complete Specification Left, 16th- Oct., 1893-Accepted, 2nd Dec., 1893
PROVISIONAL SPECIFICATION.
Improvements in or connected with Turning Lathes.
We, WILLIAM TAYLOR, THOMAS SMITHIES TAYLOR and HERBERT
WILLIAM HOBSON, all of Slate Street, Leicester, in the County of Leicester,
Scientific Instrument Makers, do hereby declare the nature of this invention to be
as follows:-
Our invention relates to means of setting accurately the tool of a turning lathe
when it has to turn to a certain diameter or has to be guided by a rubber on the
slide travelling along a template or pattern, and to an inexpensive construction of
such templates or patterns to suit various forms of work to be turned in the lathe.
For this purpose, we provide a gauge which may be attached to the lathe mandril
by inserting it in the conical hole usually made to receive centres, this gauge
consisting of a projecting cylindrical part of some known radius such as a quarter
of an inch, and having at its side and at its free end a projecting piece the inner
edge of which coincides exactly with the periphery of the gauge and is therefore
at the same radial distance from the centre. Before beginning to turn, we put the
transverse slide of the rest in some position determined by a stop or otherwise, and
we fix on it the tool with its turning point touching the gauge, which thus deter-
mines the radial position of the tool. On now moving the slide to turn the work,
we know that the radius of the work so turned must be inch greater or less
than the distance of the slide from its original position according as the tool had
been originally set to touch the outside of the gauge or the inner edge of the piece
projecting from it.
In like manner, when a template or pattern is employed to govern the movement
of the slide, we make or set on the template a stop, shoulder or mark which
determines the position of the slide when setting the tool to the gauge, and its
relative position when turning to any desired diameter.
Instead of shaping, for each form or size of article to be turned, a template or
pattern in one piece presenting on its edge the stops or guides for the slides
carrying the tool, we employ a variable template consisting of a graduated metal
blade along which we can slide longitudinally or transversely, or both ways, another
blade or piece, or several of these, which may also be graduated and fixed where
desired by setting screws or otherwise.
Dated this 17th day of January 1893.
ABEL & IMKAI,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in or connected with Turning Lathes.
We, WILLIAM TAYLOR, THOMAS SMITHIES TAYLOR, and HERBERT
WILLIAM HOBSON, all of Slate Street, Leicester, in the County of Leicester,
Scientific Instrument Makers, 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 :-
Our invention relates to means of setting accurately the tool of a turning lathe
when it has to turn to a certain diameter or has to be guided by a rubber on the
slide which carries the tool travelling along a template or pattern. Our invention
relates also to an inexpensive construction of such templates or patterns to suit
D
037

page_text: various forms of work to be turned in the lathe. We shall describe our invention
referring to the accompanying drawings.
We provide a gauge, such as is shewn in Figure 1, which can be attached to the
mandrel or back centre of the lathe by inserting it in the conical hole usually made
to receive a removeable centre, such as that shewn in Figure 2.
The gauge,
Figure 1, has a cylindrical part A of some known diameter such as half an inch,
giving radius one quarter of an inch. It may also have at its side a projecting
piece B the inner edge of which coincides exactly with the periphery of A, and would
therefore, when A has inch diameter, be inch distant from the axis of the lathe.
As the projecting piece B can sometimes be dispensed with, the lathe centre
Figure 2 having a cylindrical part A¹ turned or ground accurately to some known
diameter such as an inch, may be used as the gauge.
A
Before beginning to turn we put the transverse slide of the slide rest in some
position determined by a stop or mark and we fix the tool in the rest with its
turning point touching the gauge which thus determines the position of the point
of the tool relatively to the axis of the lathe. We can now move the slide along a
graduated scale, or as determined by a graduated wheel on its screw, to such
position as may be necessary to turn the work to any desired diameter, as may be
readily understood by referring to the plan Figure 3 and end view Figure 4 of a
slide rest with tool adjusted as above described. The gauge A' is in this illustration
the back centre of the lathe which the point T of the tool is set to touch.
vernier scale V is fixed to the side of the transverse slide of the rest and a sliding
scale S is adjusted in a dovetail groove formed in the base of the rest in such a
position that the vernier zero exactly coincides with a division of S corresponding
to the radius of the gauge A1. As dimensions are usually given in diameters and
not in radii, we prefer to graduate the scale S to half full size, so that we can read
diameters upon it. On now moving the slide and with it the vernier V until it
points on the scale S to a certain diameter, we know that the point of the tool will
turn the work to that diameter. In this case we have shewn a tool suited for
outside turning, but obviously the same arrangement is applicable for internal
turning. Instead of using the scale S and vernier V there might be a graduated
wheel on the screw of the rest and a pointer, with or without vernier divisions, fixed
on the base of the rest.
When the tool is to be guided by a template we arrange the parts as shewn in
plan in Fig. 5.
In this case the gauge is set in the centre hole of the mandrel M and the template
or pattern P is fixed in a convenient position on the lathe bed. The transverse
slide, which in this case may be moved by a hand lever L, has a bracket or arm
carrying a rubber R which is brought to bear against a stop or shoulder. of P when
the tool T is fixed so that its point is touching the edge of the gauge B. The
shoulder of P against which R bears being in coincidence with the edge of B as to
radial distance from the axis of the lathe, the article will be turned to the shape
determined by P and in all parts to diameters corresponding to the projection of the
contour of P beyond the axial line of the lathe. Obviously the arm carrying the
rubber R might be lengthened or shortened, the position of P being altered to
correspond.
In many cases, instead of shaping, for each form or size of article to be turned, a
template or pattern in one piece presenting on its edge the stops or guides for the
slide carrying the tool, we can employ a variable template such as is shewn, in plan
as seen from above in Fig. 6, and as it would be seen inverted in Fig. 7. Two plates,.
an upper D and a lower E are held together by a pair of bolts engaged in holes
slotted in the one plate at right angles to the slots in the other, so that the two
plates can be adjusted transversely and longitudinally in relation to each other and
clamped by the bolts. A rubber such as that marked R in Fig. 5 being set to bear
against the face F when the tool is set to touch the gauge, then the rubber in
travelling along the faces G, H, I will turn an article to the diameters and with the
shoulder determined by these faces, which may be varied within certain limits by

page_text: the relative movements of the plates D and E. In like manner for inside turning
the rubber may travel along the opposite faces G, H, I'. We prefer to apply
verniers V V to the scales S S₁, and, to allow for the lateral movement of E, we
extend the divisions of its scale S₁ in parallel lines. A. diagonal scale S may also
be used for reading the fractions of each division as E is moved laterally.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. The herein described method of adjusting the tool of a turning lathe in
relation to the axis of the lathe, so that on moving the slide carrying the tool as
determined by an index attached to the slide moving along a fixed scale or by a
rubber attached to the slide moving along a fixed template or pattern, the diameter
of the article turned shall correspond always with that indicated on the scale or
determined by the template.
2. For operating in the manner above referred to, the combination with a lathe
and its slide rest of a gauge inserted in the mandrel or back centre, and index or
rubber attached to the transverse slide of the rest, and a fixed scale or template,
substantially as described.
3. A variable template substantially as described with reference to Figs. 6
and 7.
Dated this 14th day of October 1893.
•
ABEL & IMRAY,
Agents for Applicants.