AN IMPROVED STEADYING POPPET FOR LATHES
Year: 1884

page_text: We, THOMAS HENRY OWEN and ALEXANDER KELLAR, of Bute Docks, Cardiff,
Engineers, do hereby declare the nature of our invention for "AN IMPROVED
STEADYING POPPET FOR LATHES," and in what manner the same is to be performed
to be particularly described and ascertained in and by the following statement:-
The object of our Invention is the construction of an improved steadying poppet
for use with lathes, boring machines, and other similar machine tools.
It is a matter of common experience that, in turning long shafts and performing
other similar operations upon long work, unless the work be kept truly in line with
the advance of the cutting tool, the pressure of the latter upon the work will suffice
to bend it, and, consequently spoil it by cutting it unequally.
Our invention produces a steadying poppet easily applicable to any type of lathe
or boring machine, and is so constructed that it is easily and accurately adjusted to
work of any diameter, which it will keep truly in line so long as the cut is on.
In order that our invention, and the method of putting the same into successful
operation, may be thoroughly understood, we will proceed to describe the same,
reference being made to the accompanying drawings, which are to be taken as part
of this specification and read therewith. The same part is, throughout the figures,
marked with the same reference letter.
Figure 1 is a transverse elevation, partly in section, of our improved steadying
poppet adapted to a shaft turning lathe.
Figure 2 is a side elevation of the same.
Figure 3 is a plan of the same, omitting the shaft.
A foundation plate, B, is secured to the bed, C, of the lathe, or other machine
tool, and is made fast, preferably by V strips, b, and bolts or studs, b¹.
On the centre of the foundation plate, we form a strong boss, D, bored out to
receive the guide, E, of the poppet, which slides vertically therein. A nut, F, on
the guide, and resting upon the top of the boss, regulates the height of the
frame, A, I, of the poppet. The guide, E, is fixed, at any point, by the set
screw, G, the point of which enters the groove, g, in the side of the guide.
The frame of the poppet consists of two pairs of vertical horns, or cheeks, A,
forming a cradle, slotted out, for a sufficient length, to admit the bridge piece, I,
and to allow of its being closed up towards the axis of the work, or to be extended
Diss 71

page_text: therefrom, as far as the slots, c', will allow. The bridge piece, I, is fixed at the
necessary height, by means of bolts and nuts, C, passing through its ends and
the slots, c¹.
The method of using our improved steadying poppet is as follows.
The shaft having been centred, the guide, E, is adjusted until the inclined
planes, a, of the cheeks, A, bear truly upon the under surface of the shaft when the
latter is truly horizontal. The bridge picce is next adjusted so that its inclined
planes, i, will bear equally upon the upper surface of the shaft. We do not confino
ourselves to any particular angle that the two planes, i, i, or a, a, must make with
each other, provided that a vertical line passing, through the centre of the work
bisects both angles equally.
Instead of making the surfaces i, i, a, a, straight as drawn, we may make them
arcs of large radius, without departing from the essence or substance of our
invention.
Although the drawings illustrate the application of our steadying poppet to a
shaft lathe, it can be adapted to any similar machine tool, e.g. a boring machine.
We show, in dash-and-dot-lines, in Figure 1, another form of our steadying
poppet. The slotted cheeks of the frame, A, are not vertical, but inclined, and
receive the extended ends of the saddle piece, I, which is capable of being adjusted
upon two vertical screws, j springing from the foundation plate, B, by means of
two pairs of nuts, k, k. This modification does not affect the adjustment of the
guide, E.
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 :—
The combination of the two surfaces, i, i, either inclined planes or arcs, of a
bridge piece, I, with the two surfaces a, a, either inclined planes or arcs, of a
cradle, A; both bridge piece and cradle being adjustable as to the axis of the
work to be machined, substantially as herein described, with reference to the
accompanying drawings.