Improvements in the Method of Manufacturing Sheet Metal Pulleys.
Year: 1896

page_text: Date of Application, 6th Jan., 1896-Accepted, 23th Mar.. 1896
COMPLETE SPECIFICATION.
Improvements in the Method of Manufacturing Sheet Metal
Pulleys.
I, OLIVER WILLIAM KETCHUM, of 323 King Street West in the City of
Toronto, in the County of York, in the Province of Ontario, Canada, Manu-
facturer, 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 a certain new and useful improvement in the method of
manufacturing sheet metal pulleys and the object of the invention is to provide au
expeditious and perfect method whereby the pulley may be completely formed up
and finished and it consists essentially in the various steps hereinafter more
particularly explained.
Figs. 1, 2, 3, 4, and 5 represent the form of the blank during the various steps
of the method.
Fig. 5 shows a form of crowning the pulley.
In the drawings like letters of reference indicate corresponding parts in each
figure.
In making the pulley a circular blank of sheet metal (see Fig. 1) is drawn up in
a suitably designed press. Strengthening beads are formed in the web and a hole
or holes for the insertion of and securing of the hub in position are punched in the
centre of the web (see Fig. 2).
Dies and punches suitable for this work are shown and described in my former
Patent No. 13783 dated the 17th day of July 1894. The rough edge of the
drawn up blank is then trimmed by means of a pair of rotary shears (see Fig. 3).
The inner cutting wheel of the shear is made with a flange below and diametrically
outside the cutting edge, so that the edge of the blank is slightly turned in while
being trimmed. The trimmed blank is then placed in a press and an inwardly
turned bead is formed on the outer edge of the peripherial face (see Fig. 4).
Dies for forming this bead are shown and described in my said former Patent
No. 13783.
To crown the peripherial face shown in Figs. 5 and 5^ it is necessary to bend
the peripherial face of the pulley either in a suitably designed rolling machine or
by outwardly expanding dies in a press as shown in my said former Patent
No. 13783.
An alternative form for crowning the pulley may be used either for a single but
preferably for a double pulley as shown in Fig. 54 in which cup-shaped dies are
used. The crowning is then accomplished by bringing the dies together thereby
slightly compressing the outer edges of the peripherial faces of the pulley as
shown. The hub of the pulley may at any suitable stage of the process be secured
to the web. The hole in the hub is of course bored out smooth concentric with
the peripherial face of the pulley when the pulley is finished.
Having now particularly described and ascertained the nature of my said inven
tion, and in what manner the same is to be performed I declare that what
I claim is,
1. The method herein described by which a pulley is made out of a single piece
of sheet metal consisting first in cutting the blank into a circular form then

page_text: forming it up into a web with a peripherial face or rim integral therewith and
substantially at right angles thereto and a hole or holes in the web for securing
the hub thereto then trimming the rough outer edge of the formed up blank so
that the trimmed edge may be turned slightly inwardly then beading such edge
then crowning by suitable means and finally inserting the hub into the central
hole of the web and suitably securing the flanges of the hub to the web as set
forth.
Dated the 6th day of January 1896.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London, Agents for the Applicant.