Improvements in Tube Expanders.
Year: 1896

page_text: Date of Application, 2nd Mar., 1896-Accepted, 4th Apr., 1896
COMPLETE SPECIFICATION.
Improvements in Tube Expanders.
I, ALFRED FERNANDEZ YARROW, of Isle of Dogs, Poplar, in the County of
London, 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 the construction of tube expanders and the arrangement
of gear for working them as I shall describe referring to the accompanying
drawings.
Fig. 1 is a plan, Fig. 2 is a longitudinal section and Fig. 3 is a transverse section
on the line Z Z of Fig. 1 of a tube expander according to my invention, with
handles for holding, and pulley for driving it by a band.
Fig. 4 is a side view and Fig. 5 is an end view, drawn to a smaller scale, showing
worm gear and flexible revolving shaft for driving it.
A is a tubular stem, which is preferably slotted longitudinally, the edge of the
slot being graduated. To the stem A is attached a socket piece B, having three
longitudinal slots occupied by rollers C arranged around a taper mandrel D.
The slots for the rollers Care not parallel to the axis but slightly inclined to it,
so that, as the socket piece B revolves carrying the rollers with it, they being
caused to rotate around their own axes, draw the mandrel D forwards, and, owing
to its taper are gradually pressed radially outwards.
The operator by observing the division of the scale to which the hend E of the
mandrel is thus advanced can ascertain the exact diameter to which the interior of
the tube is expanded.
When a number of tubes have to be expanded to exactly the same diameter, a
setting screw E' may be inserted in one of a number of screwed holes in the
stem A, so as to arrest the head of the mandrel D when it has been so far
advanced.
The end F of the stem takes its bearing in the eye of a double handle H which
is held by the two hands of the operator, while the expander is caused to revolve
by a band connecting a pulley G to the pulley of some convenient motor.
As shewn in Figs. 4 and 5 the double handle H is made with a pair of bearings K
for the expander spindle, and a pair L for the spindle of a worin M which gears
with a worm wheel N on the spindle of the expander.
The worm M is driven by a flexible shaft P from some convenient motor.
worm might also be driven by a band pulley.
The
The flexible shaft, instead of driving the worm, might drive the expander direct,.
thus taking the place of the pulley and band shewn in Fig. 1.
Also where electrical energy is available, an electro motor may be mounted on
the handle, having its armature fixed on or geared to the spindle of the
expander.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A tube expander having rollers bearing on a taper mandrel and held in slots
of a socket piece which are slightly inclined to the axis of the mandrel, substantially
as described.
2. In a tube expander such as is above referred to the means herein described of

page_text: determining the extent to which the tube is expanded by observing the position or
arresting the advance of the mandrel hend.
3. In combination with the expander and means of driving it a double handle
having a bearing for the expander spindle, substantially as described.
4. In combination with the expander and a worm wheel thercon, a double handle
having bearings for the expander spindle and for the spindle of a worm which
gears with the wheel on the expander, and is driven by a flexible shaft, substantially
as described.
Dated this 2nd day of March 1896
ABEL & IMRAY,
Agents for the Applicant.