Improvements in the Construction of Chains, chiefly applicable to Velocipedes.
Year: 1893

page_text: Date of Application, 5th Aug., 1893
Complete Specification Left, 5th May, 1894-Accepted, 21st July, 1894
PROVISIONAL SPECIFICATION.
Improvements in the Construction of Chains, chiefly applicable to
Velocipedes.
I, ROBERT WALKER SMITH of Laurel House, Astwood Bank, near Redditch
Works Manager to the Eadie Manufacturing Co., Hunt End Redditch do hereby
declare the nature of this invention to be as follows:-
This invention relates to the rivets for chains. The novelty consists of a method
to harden the centre, and leave the ends soft where they are riveted to side links,
by this means I improve and simplify the present construction of chain making.
To accomplish my object I use preferably a quality of wire, which I cut into lengths
and case harden, which converts the outside diameter of the wire to steel: this is
taken from the muffles and allowed to anneal. The wire is then shouldered or
machined down, thus removing the steel coating at each end. The rivets are then
beated and placed in oil or water, which leaves them hardened in the centre or
frictional part of chain, the ends where the outside diameter has been reduced soft
and maleable which enables them to be riveted to side plates.
Dated this 4th day of August 1893.
COMPLETE SPÉCIFICATION.
Improvements in the Construction of Chains, chiefly applicable to
Velocipedes.
I, ROBERT WALKER SMITH, of Laurel House, Astwood Bank, near Redditch,
Works Manager to the Eadie Manufacturing Company, Hunt End, Redditch, 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 the rivets for chains and particularly those chains which
are used for transmitting power and motion in velocipedes and this invention consists
of the hereindescribed method of making the said rivets hard at the central portion
on which the link turns and soft at the end portions where the rivets are rivetted
to the side links. By my invention as hereindescribed I improve and simplify the
present construction of chain making.
I will describe my invention by referring to the accompanying drawing on which
Fig. 1 represents a piece of wire from which one of the rivets has been partly
formed;
Fig. 2 shews one of the said rivets which is of ordinary shape;
Fig. 3 represents in part sectional elevation and Fig. 4 in part sectional plan a
piece of cycle driving chain with the rivets made in accordance with this invention.
The same letters of reference indicate the same parts in all the figures of the
drawing
In carrying out my invention I use a good quality of smooth drawn iron or steel
wire of a suitable quality to case harden and which will not be hardened by being
merely heated and cooled in oil or water. This wire I cut into suitable lengths of
say about eighteen inches or they may be longer or shorter if desired and these
lengths of wire I subject to any well known case hardening process which converts

page_text: steel
the outside surfaces of the wires to a steel having the necessary properties to harden
by case hardening. I then take the wires from the case hardening muffle_and
allow them to cool gradually so as to be annealed and soft when cold. From these
lengths of wire I form the rivets by shouldering or machining down the wire at the
parts marked a¹ a' see Figs. 1 and 2 thus removing the "case hardened
coating from these end portions a' a² which fit in the side links B' B' of the chain.
The rivets A after being shouldered down and cut off from the length of wire are
then heated and dipped into oil or water thus causing the enlarged central steel
coated portion marked c to be hardened so as to resist the wear of the link D which
turns upon it but as the steel surface has been removed from the end portions a¹ a
these remain soft and malleable which enables them to be rivetted to the side
links B¹ B³.
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 hereindescribed method of making a chain rivet with a case hardened
central portion to resist wear and with soft end portions for rivetting to the side
links of the chain, the said method consisting in first converting (by case hardening)
the outer surface of the iron or steel wire to a steel baving the properties to harden
then removing the case hardened steel coating from the end portions of the rivet
which fit in the side links and finally hardening the steel surface of the central
portion by heating the rivet and cooling the same suddenly, substantially as herein-
before described.
1
2. The manufacture and sale of the improved chain rivets made in the manner
herein set forth with an enlarged central case hardened portion to resist wear in
combination with soft end portions for rivetting to the side links.
3. Jointed liuk chains for velocipedes and for other purposes having their rivets
made with case hardened central portions and with soft end portions for the purposes
and in the manner substantially as hereinbefore set forth.
Dated this 4th day of May 1894.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.