Improvements in Chains.
Year: 1899

page_text: Date of Application, 31st Oct., 1899-Accepted, 6th Jan., 1900
COMPLETE SPECIFICATION
Improvements in Chains.
I, REGINALD HADDAN, of the Firm of Herbert Haddan & Co., of 18, Bucking-
ham Street, Strand, W.C., London, Patent Agent, do hereby declare the nature of
this invention, a communication to me from abroad by The Plano Manufacturing
Company, of 1110, Chamber of Commerce Building, Chicago, Illinois, United
States of America, and in what manner the same is to be performed to be par-
ticularly described and ascertained in and by the following statement:-
-
This invention relates to an improved construction for links for sprocket and
similar chains and consists in making the body of the link of such a shape as
will prevent the constant whipping of the chain upon the chain tightener, and
also the wearing off of the nose of the hook of the links thereon, together with
the tendency to cut into the sheathing sometimes employed in connection with
such chains.
Referring to the drawings, in which the same letters of reference are used to
designate identical parts in all the figures,
Fig. 1 is a side elevation of a pair of sprocket wheels connected by a chain
embodying this improved construction, and also showing the position of the chain
tightener and the sheathing beneath said chain;
Fig. 2 is a side elevation showing a portion of the old style chain as it is
applied to a belt tightener on the under side thereof;
Figs. 3 and 4 are bottom and top plan views respectively of single links of
the chain;
Fig. 5 is a cross section thereof on the line 5-5 of Fig. 1; and
Fig. 6 is a view similar to Fig. 2, except that a portion of my improved chain
is shown.
In almost all machinery in which sprocket or similar driving chains are
employed some form of a chain tightener is necessary, and it must be applied
to the outside of the chain. As will be seen from the ordinary construction of
the chain shown in Fig. 2, the nose A of the hook B comes directly in contact
with the surface of the anti-friction roller or chain tightener wheel C, and this
causes considerable wear upon the nose in case the ordinary anti-friction roller
tightening device is used, and still greater wear in case a rigid or non-rotating
frictional device is employed. This soon results in wearing off the nose as seen
in the link to the left in Fig. 2 at A¹. As is well known, in the construction
of this type of detachable links, the interior surface of the hook comprises some-
what more than a semi-circle so that the greater interior diameter of the hook is
greater than the width of the opening thereof. In assembling these chains, the
links are turned to a position where the reduced portion D of the link can slip
through the opening in the one abnormal position, while when they are moved
to the normal position, the links are securely connected. By referring again to
the worn off nose at A¹ in Fig. 2, it will be seen that when it is thus worn off
the interior portion of the hook is reduced to substantially a semi-circle so that
there is a possibility of the links parting in their normal position in case any

page_text: whipping motion or slight disturbance should occur. Consequently, with this old
style of a hook and body of the chain, the links soon become worn out.
Another objection to this form of construction arises from the fact that at the
time the nose of the hook is in contact with the friction wheel of the chain
tightener, the body of the link is at some distance therefrom, but as soon as it
has advanced a little bit, the body of the chain is swung down into contact with
the friction wheels, thus producing a continual whipping motion of the chain,
which tends to wear out the bearings of the link and break it down, while any
wear of these bearings increases the trouble pointed out in connection with the
wearing off of the nose, as well as being annoying on account of the noise
produced.
This invention is designed to remedy both of these defects, and at the same
time to produce a light, yet strong and substantial, chain. This result is produced
by forming the outer sides of the links with the curved surface E, which projects
beyond the plane of the nose A, so that when the chain is running along on the
surface of the sheathing F, the nose is protected from any material contact there-
with. Of course, it will be understood that it is not necessary to have so great
a clearance between the nose and the sheathing as represented in the drawings,
the principle of the device being that the shape of the link shall be sufficient to
protect the nose from wearing contact with the sheathing.
The same principle and method of operation occurs in connection with the
contact of the nose with the anti-friction rollers or chain tighteners C, and by
reference to Figs. 1 and 6, it will be seen that all the wear is completely pre-
vented. This construction, it will be further observed, also prevents the whip-
ping of the chain previously mentioned.
To prevent the reciprocal wear upon the chain tightener and sheathing, and
upon the body portions E of the links becoming a serious matter by reason of
the links being so shaped as to form a small contacting surface at E, the cross
section of the chain is formed as shown in Fig. 5, where the thin vertical web G
is reinforced by the flanges H, which are of sufficient width to give additional
strength and bearing surface to the contacting portions of the chain.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, I declare that what
I claim is:
1. In a detachable link chain, a link having one end formed with a bearing
hook, and the opposite end with a cylindrical bearing co-operating with the hook
of the adjacent link, and its outer side formed with swelled curved portions pro-
jecting into the plane of the nose of the hook to protect it from contact with a
chain tightener or similar article, substantially as and for the purpose described.
2. In a chain, a link having its side bars formed with thickened portions or
flanges upon their outer side, substantially as and for the purpose described.
3. In a chain, a link having its side bars consisting of the thin vertical web G
and the curved strengthening flanges H, substantially as and for the purpose
described.
Dated this 31st day of October 1899