Improvements in Wood Pulleys.
Year: 1892

page_text: Date of Application, 30th June, 1892-Accepted, 30th July, 1892.
COMPLETE SPECIFICATION.
Improvements in Wood Pulleys.
We, ROBERT KERR and TOM JUBB, both of Square Road, Halifax, in the
County of York, Belting Manufacturers and General Mill Furnishers, and HENRY
ALEXANDER COLE, of 4, Drury Lane, Liverpool, in the County of Lancaster,
Managing Agent, 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:-
This invention relates to improvements in wood split pulleys.
As at present constructed, they are, we believe, mostly built in segments and put
together with glue and sulphur, rendering them unsuitable for working in moist or
warm places.
Now the object of this invention is to provide a wood pulley which can be built
up without the use of either glue, sulphur or the like, and which is adapted to work
satisfactorily anywhere, either in damp or heat, and is also much lighter than metal
pulleys and easily secured to the shaft. We also employ hard wood in the
construction of the said pulleys, which renders them extremely durable.
The invention will be best understood by referring to the accompanying drawings,
in which-
Figure 1 is a perspective view of a belt pulley.
Figure 2 is a perspective view of a simpler form of construction.
Figure 3 is a perspective view of a rope pulley.
Figures 4, 5 and 6 are details.
Figure 7 is a perspective view of a make of pulley when its rim is made of more
than two parts or sections.
A, is the rim formed of bent wood (steamed and pressed to shape), the rim is
preferably made of two halves as shown in Sheet 1 of the drawings, we do not,
however, limit ourselves to this number of parts or sections, as, if desired, the rim
may be made in quarters or any other number of pieces, as shown on Sheet 2;
B, cross pieces secured to each half of the rim in any suitable manner, preferably
by means of a screw b, as shown in Figure 4, said screw being placed in a recess C
in the rim and the recess may be filled up with a block c of wood, or the cross piece
may be dovetailed into the rim, as shown in Figure 5, and, where a dovetail or
tenon fastening is employed, screws, such as b, may also pass through the rim into
the dovetail or tenon.
In small pulleys, the cross pieces B would be sufficient without the addition of
spokes, see Figure 2, but, in larger ones, it may be preferable to add two or more
spokes as shown at J in Figures 1 and 3.
This improved pulley can be fitted to shafts of different diameters and held by
compression only, so dispensing with keys or set screws.
Figure 6 is an enlarged view of a bush, the external diameter of which exactly
fits the hole D, but the internal diameter can be varied in the different bushes to
suit different shafts.
The rope pulley, Figure 3, has preferably a groove and tongue G formed in the
rim where the two halves meet, but this groove and tongue method of fastening
the parts of the rim is not confined to rope pulleys only, it can be equally well
applied in the case of other pulleys.
E are bolts, by means of which the two halves of the pulley are held together
and by which they are secured to the shaft, or, when bushes M, Figure 6, are
employed, by means of which the pulley with the bush is secured to the shaft.
In the construction of these pulleys, we make use of hard wood, such as hickory,

page_text: maple, rock elm, etcetera, whereby we secure a smooth regular surface that is very
durable in wear and gives great gripping power.
Where the rim of the pulley is made or composed of more than two parts or
sections, as in. Figure 7, it may be desirable, instead of using two cross pieces B,
one to each half, to employ a cast metal bracket K, in two parts to clasp each side
of the shaft or bush by means of bolts k, k, and provided with little boxes A into
which the ends of the pulley spokes take. L are little fastenings to make the joints
of the rim sections more secure.
We do not confine ourselves to the exact shape of the cross piece B shown in the
drawings, as they can be made in a variety of ways without departing from the
spirit of the invention, and the rim, too, may be of different sections to suit different
purposes, such as flat for belt driving, curved and grooved for rope driving, etcetera.
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. A pulley consisting of a bent wood rim formed in two or more parts and
having cross pieces secured to each half of the rim, provided with means, such as
bolts, passing through them, whereby the two halves are held together and the
pulley readily secured to the shaft, substantially as described.
2. The general arrangement and construction of parts forming the improved
wood pulley as shown and described with reference to Sheet 1 of the drawings,
substantially as hereinbefore described and shown.
Dated this 29th day of June 1892.
WM. P. THOMPSON & Co.,
Of Liverpool, Manchester, Nottingham and London, Patent. Agents.