An Improved Expanding Pulley.
Year: 1893

page_text: Date of Application, 14th Oct., 1893-Accepted, 24th Mar., 1894
COMPLETE SPECIFICATION.
An Improved Expanding Pulley.
We, ANDREW GIVEN, Paper Merchant, and CHARLES BOWTELL SMITH,
Bookbinder, both of Dunedin, in the Colony of New Zealand, 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:-
The principle in the design of this pulley is that two cones or pulleys with
conical rims are divided into a number of equal parts, tending towards the centre,
each alternate part being cut away; these cones can be made to interlace by being
turned in opposite directions, when it will be found that when they are placed
closer together a smaller pulley is obtained while when drawing them further
apart a larger pulley is obtained, within the limits of the sizes of the cones, and
these may be secured at any point within such limits; this pulley may be made so
that it is perfectly balanced in every part when so required, for high class and quick
speed machinery and it can be used both for the purpose of altering the speed of a
machine or any part or parts of the same readily; or merely for the purpose of
tightening the belting, when, if the speed is required to be about the same, or if
otherwise found necessary, two pulleys may be used to each helt.
Referring to the accompanying drawing;
Fig. 1 is an end view, and Fig. 2 is a sectional elevation of a small size complete
pulley;
Fig. 3 is an end view of one of the halves of the same pulley, to shew the
construction more distinctly;
Fig. 4 is a sectional elevation of a large pulley shewing another method of
applying the same invention.
Similar letters refer to similar parts as far as such parts are common.
A, A, shew one side or set of wings; and B, B, shew the other side or set of
wings, in a complete pulley, these may be plain so that they may be turned and
fitted all over if desired, as shewn Fig. 3, or may be strengthened in any way
desired or in such a way as is shewn by webs at the back of each wing see B, B,
Fig. 1, and A, A, B, B, Fig. 2.
The pulleys may have any number of wings such as are shewn in Fig. 1, and
Fig. 2, and Fig. 3, where the number shewn is seven, as can be best seen in
Fig. 3, A, A, and these wings may be set at any angle required; or be of any other
shape than straight; if so desired.
The cones may also interlace each other from either end.
The pulleys may also be secured in any manner to the shaft; such as by a right
and left handed screw, and secured by lock nuts (such as the nut E) Fig. 2, or the
one half of the pulley may be secured in any way to the shaft, or be loose so as to
revolve on it; and the opposite side, or wings, may be screwed with any number of
screws or may be otherwise fastened to it (such as A and B) Fig. 4, where A and B,
are made so that they may be opened apart, or closed together by the screws D, D,
of which there may be any number, thus effecting the same purpose.
pulleys may be of any design as far as the general outline is concerned; and may
be made of any suitable size and of any suitable materials.
And these
These pulleys may be used in combination with an attachment to a paper ruling
machine or for any part of any other machine either as an expanding pulley or
for tightening the belting or as a grip pulley for which it is well adapted.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In an expanding and contracting pulley, the combination of the double cones,
in any suitable form, substantially as shewn on drawing and described herein; so
arranged that the cones, being cut out alternately (such as Fig. 3,) may be made
capable of interlacing (as shewn Fig. 1) and be capable of being moved inwards or
outwards (as shewn Fig. 2) so as to decrease or increase the working face of the
pulley.
2. In an expanding and contracting or grip-pulley, the cones or wings, capable
of being moved toward or away from each other and of being kept in the desired
position by means substantially as herein described and shewn (Fig. 2 and Fig. 4)
or by other suitable means; and any mere modification for adapting existing
pulleys to contract and expand, in the manner herein set forth, for use as grip-
pulleys.
Dated this 22nd dow of May 1802
ANDW. GIVEN.
CHARLES BOWTELL SMITH.