Improvements in Chains.
Year: 1893

page_text: Date of Application, 24th Jan., 1893-Accepted, 25th Feb., 1893
COMPLETE SPECIFICATION.
Improvements in Chains.
I, LUDWIG HERMAN, of 29 Euclid Avenue, Cleveland, Ohio, United States of
[ America, Mechanical Engineer, do hereby declare the nature of this invention and
in what manner the same is to be performed to be particularly described and ascer-
tained in and by the following statement :-
This invention relates to certain new and useful improvements in chains, the
invention having for its object the construction of a chain adapted for use in
hoisting, hauling loads, transmitting power, as chain cables, and all such other uses
and purposes wherein the flexibility of the chain at all its joints is an essential
feature.
To this end, my invention consists in constructing the link of four separable parts
adapted to be assembled together to form a complete link, all as more fully herein-
after described and specifically pointed out in the claims.
The links of chains as ordinarily made, are formed from round iron bent to an
elliptical shape, their ends being scarfed and welded together. It is a well known
fact that chains thus made are often defective at the weld, either on account of
imperfect welding or on account of the iron being overheated and burned until it
loses much of its strength. Again, the strains in the side of a link are tensile, and
require a tough tenacious metal that will stand appreciable elongation without
rupture, qualities found in soft iron and mild steel. The round ends of the links
are subjected to transverse and shearing strains as well as abrasion by the action of
the links upon each other and in passing over sheaves and drums. Hence, for this
end part of the link, the material should be harder than the other so as to endure
the wear and strain that comes upon it.
By the peculiar construction of my link, the end pieces are beams fixed at both
ends and loaded in the middle. The strain in such an element of construction is
definite and easy to determine. The same applies to the strains in my side pieces
which are strictly tensile throughout their entire length.
It is a well known fact that, in the chains as ordinarily constructed, a very large
percentage of the breaking occurs at the quarters, which is a convincing proof that
it is at the ends of the links where lies the weakest points whether at weld-quarter,
butt-quarter or both, and it is the especial object of this present invention to
overcome this and other well known objections in chains.
In the accompanying drawing,
Figure 1 is side elevation of a sprocket wheel partly broken away at the top
to disclose the relation of the teeth to the chain and showing a section of chain upon
said wheel.
Figure 2 is a side elevation of one of my improved links having a portion of the
upper yoke broken away to show the threaded side bar therein, and showing a cross
section of a connecting yoke or link in its upper portion.
Figure 3 is a cross section of a side bar on line x-x in Figure 4.
Figure 4 is an edge view of my improved link.
Figure 5 is a side elevation in detail of one of the side bars.
As each link of my improved chain is constructed or built up of duplicate parts, a
description of one link is deemed sufficient.
The ends of the links consist of yokes A, substantially of the form shown; the
ends of the yokes terminate in enlarged heads forming shoulders a, and these heads
are interiorly threaded at right angles to the length of the yokes to receive the
ends of the side pieces, as hereinafter described.
These yokes may be cast in any suitable metal or alloy, or may be forged in
suitable moulds by pressure or by, means of drop-forging, and of such strength and
hardness as shall best adapt them to the purpose they may be specially designed for.

page_text: The preferred form of cross section at the point where the yokes cross, when
assembled in the chain, is shown in Figure 2, but this form may be varied without
departing from the spirit of my invention.
By making the yokes substantially of the form shown at their ends, the chain
built up will be effectually prevented from becoming entangled and the employment
of the "studs" does not become necessary. The enlargements at the ends of the
yokes not only gives strength to such yokes where the side pieces enter, but they
serve to form a bearing for the link when it is used on a drum or sheave, thus
preventing the bending of the link, and this is clearly illustrated in Figure 1, where
the shoulders at each end of the link rest on the sheave, the centre or side pieces of
r the link being free.
Should the chain be used on a sprocket wheel, the sprockets would come in
contact with the spherical or convex surface d, and this would spread the contact
with the sprocket over a considerable surface thus diminishing the wear at that
point. This surface may be hardened if desired.
B represent the side bars of the links, and are shown as having flat sides b, but,
while this is a preferred form for these bars, I do not desire to limit myself to any
shape thereof, in cross section.
It will be observed that the side pieces are reduced in cross section between their
ends, while their threaded ends are enlarged. This construction makes the inter-
mediate portion of the side pieces the point of greatest weakness, and enables the
artizan to calculate with the utmost exactness just what the strength of a given size
of chain will be. It will also be observed that there is practically no limit to the
size of chain that may be constructed on this principle, and the sizes may be run
from inch or less to several inches, in the cross-section of the side bars, the yokes
in all cases being of proportionate strength.
The threads on the ends of the side bars are cut right and left so that they may
be screwed into the ends of the yokes when turned in one direction.
This construction admits of ready adjustment of the pitch should any link become
elongated through continued use; or the replacing of a side bar or yoke should one
become defective, and every facility is provided for splicing, lengthening or
shortening the chain at any point within the length of the chain.
Another advantage in my construction is, that by the cross section shown in the
yokes or end pieces, the radius of the bearing surface is considerably larger than in
a link made of round iron of equal weight, hence, this bearing surface being thus
enlarged, the abrasion of the links upon each other is materially reduced.
The construction of my link is such that each part, as well as the entire chain,
can be made by automatic machinery especially designed for the purpose.
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. A link for a chain constructed of four separable pieces comprising two end
pieces or yokes, having enlarged ends interiorly threaded, and two side pieces whose
ends are enlarged in cross-section, said enlarged ends being threaded and adapted to
engage with the ends of the yokes or end pieces, substantially as and for the purposes
set forth.
2. A link for a chain constructed of four separable pieces comprising two end
pieces or yokes having enlarged ends interiorly threaded and provided with the
shoulders a and bearing faces d, in combination with two side pieces whose enlarged
ends are threaded and adapted to engage with the ends of the end pieces, substantially
in the manner and for the purposes, set forth.
تسم
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.