IMPROVEMENTS IN FEED MOTIONS FOR TURNING LATHES
Year: 1882

page_text: LETTERS PATENT to Thomas Shanks, Junior, of Johnstone, in the County of
Renfrew, North Britain, Engineer, for an Invention of "IMPROVEMENTS IN
FEED MOTIONS FOR TURNING LATHES.
PROVISIONAL SPECIFICATION left by the said Thomas Shanks, junior, at
the Office of the Commissioners of Patents on the 14th September 1882.
THOMAS SHANKS, Junior, of Johnstone, in the County of Renfrew, North Britain,
Engineer, "IMPROVEMENTS IN FEED MOTIONS For turning latTHES
"
This Invention has for its object to arrange and combine feed-motion details for
turning lathes in an improved manner, and so that the rate of feed can, at any
time, and without interrupting the work, be altered to any extent, with facility.
A large part of the gearing used in carrying out the Invention is carried on the
underside of an overhanging part of a saddle which is fitted in the usual way to
travel longitudinally on a single frame bed or shears or on a double frame bed.
The usual screw shaft for screw cutting, and in connection with which there is an
internally screwed or nut piece which is movable on the saddle for putting the
saddle into gear with the screw shaft or out of gear therefrom, has fast on one end
of it a spurwheel gearing with an intermediate spurwheel which gears with a
pinion on a longitudinal shaft extending along near the side of the frame bed. A
pinion on a tubular boss carried by the saddle, has the longitudinal shaft passing
through it and receives motion therefrom by a groove and feather whilst it can
move along with the saddle. The pinion gears with a spurwheel fast on a shaft
carried by the saddle, and which has also fast on it a flat faced overhung disk, and
this disk acts upon a friction pulley which is pressed against its surface and which
can be adjusted at any distance from the centre of the disk and at either side of
that centre. The friction pulley, which may consist of one or more rings of leather
or other suitable material compressed between metal disks, is upon a horizontal
shaft at right angles to that of the disk, and turns the shaft by means of a groove
and feather; whilst it is movable along it by means of a sliding block which is
I Price 8d1

page_text: adjustable by means of a screw shaft and handwheel, and which is provided with
an adjusting screw for regulating the pressure of the friction pulley against the
disk. The shaft of the friction pulley has on it a worm driving a wormwheel on
an upper horizontal shaft which through bevil wheels and a clutch drives a pinion
gearing with a spurwheel on a short horizontal shaft at right angles to the frame
bed; and this shaft has fast on it a pinion gearing with a rack fixed to the frame
bed. The friction-pulley shaft has on it at its outer end a clutch and pinion which
through intermediate spurwheels drives a pair of screw shafts serving for giving a
transverse feeding or adjusting motion to one or more slides or tool carriages upon
the saddle; and by setting the clutches as required either this transverse movement
on the saddle, or the movement of the saddle along the frame bed can be
obtained.
The parts of the gearing may be modified to suit different requirements; and in
some cases the gearing may be simplified and the longitudinal movement of the
saddle may be obtained by means of a pinion on a short vertical shaft gearing with
a rack placed with its teeth vertical.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Thomas Shanks, junior, in the Great Seal Patent Office on the
13th March 1883.
THOMAS SHANKS, Junior, of Johnstone, in the County of Renfrew, North Britain,
Engineer, "IMPROVEMENTS IN FEED MOTIONS FOR TURNING LATHES
"
My said Invention has for its object to arrange and combine feed-motion details
for turning lathes in an improved manner, and so that the rate of feed can, at any
time, and without interrupting the work, be altered to any extent with facility.
A large part of the gearing used in carrying out my Invention is carried on the
under side of an overhanging part of a saddle which is fitted in the usual way to
travel longitudinal on a single frame bed or shears or on a double frame bed. The
gearing comprises as an essential part, a frictional driving disk arranged to act on
a pulley which can be shifted so as to be driven at various speeds or in opposite
directions, and from this frictionally driven pulley gearing provided with engaging
and disengaging clutches is arranged for transmitting motion for various purposes
as hereinafter described.
And in order that my said Invention and the manner of performing the same
may be properly understood I hereunto append three sheets of explanatory
drawings to be hereinafter referred to, and representing my improve feed motion.
Figure 1, on sheet 1, of the accompanying drawings is a plan of parts of the
saddle and frame bed of a lathe, and figures, 2, and 3, on sheets 2 and 3, are
corresponding side and front elevations. In these drawings the same reference
numerals are used to mark the same or like parts wherever they are repeated.
The lathe is represented as provided with the usual longitudinal screw shaft, 4,
for screw cutting, in connection with which there is a block, 5, formed with an
internally screwed segment and which is movable on the saddle, 6, by means of a
rod, 7, and hand lever, 71, for putting the saddle into gear with the screw shaft, 4,
or out of gear therefrom. The screw shaft, 4, has fast on one end of it a spurwheel
gearing with an intermediate spurwheel which gears with a pinion on a longi-
tudinal shaft, 8, extending along near the side of the bedframe, 9. A pinion, 10,
on a tubular boss carried by a bracket, 11, extending down from the saddle, 6, has
the longitudinal shaft, 8, passing through it and receives motion therefrom by a
groove and feather whilst it is carried along by the saddle. The pinion, 10, through
an intermediate pinion, 12, on a stud, drives a pinion, 13, on a shaft, 14, carried by
the saddle; and this shaft has fast on it a flat faced overhung disk, 15, which acts
upon a frictional pulley, 16. This pulley, 16, is on a shaft, 17, carried in bearings
in an adjustable block, 18, acted on by set screws, 19, to cause the pulley to bear
with the necessary pressure against the frictional driving disk, 15. The pulley, 16,
is fitted to its shaft, 17, with a groove and feather and can be moved along the
shaft by means of a block, 20, and a screw spindle, 21, which last has an externally
projecting squared end to receive a key or handle. The speed and direction of
rotation of the frictional pulley, 16, can thus be easily varied by turning the
spindle, 21, so as to move the pulley nearer to or further from the centre of the
disk, 15, or to one side or the other of that centre.
From the frictional pulley shaft, 17, motion is transmitted by a worm 22, on its
outer end to a worm wheel, 23, on an inclined shaft, 24, (figure 2) and this shaft, 24,
by a worm, 25, and wormwheel, 26, drives a screw shaft, 27, only one end of which
is shown in the drawings but which serves for imparting a transverse surfacing
motion to one or more slide rests which are not shown. This motion can be
stopped by withdrawing the wormwheel, 26. The inclined shaft, 24, also by a pair

page_text: of bevil wheels, 28, drives a short shaft having on it a worm, 29, which gears with
a wormnwheel, 30, on a second inclined shaft having on it a worm, 31, which drives
a wormwheel, 32, on a transverse horizontal shaft, 33. A clutch movable by a
short hand lever, 34, is provided for engaging the worm wheel, 32, with the shaft 33,
or disengaging it therefrom, and the shaft is made with an externally projecting
squared end to receive a key or handle for turning it by hand. The shaft, 33, bas
fast on its inner end a spurwheel, 35, gearing with a spurwheel, 36, which is on a
short shaft having on its inner end a pinion, 37, which gears with a rack, 38, fixed
to the frame bed, 9-and through this gearing the saddle can be made to traverse
along the frame bed either by hand or by a motion derived from the frictional
disk, 15. When the saddle is being traversed by means of the rack, 38, the
block, 5, must not be engaged with the screw shaft, 4.
Having thus particularly described my said Invention and the manner of per-
form'ng the same I have to state that I do not restrict myself to the precise details
herein described or delineated but that what I believe to be novel and original
and claim as the Invention secured to me by and in terms of the herein before in
part recited Letters Patent is :-
1. The arranging or combining together of the parts of feed motions for turning
lathes in the improved manner hereinbefore described and as shown in the
accompanying drawings.
2. The combining of a frictional driving disk and adjustable pulley with other
feed motion details for turning lathes substantially in the improve i manner herein-
before descrit ed.
In Witness whereof I, the said Thomas Shanks Junior, have hereunto set
my hand and seal this tenth day of March in the year of our Lord One
thousand eight hundred and eighty-three.
Witness
EDMUND HUNT
Patent Agent.
Glasgow.
THOMAS SHANKS JR. (L.S.)