Year: 1888

page_text: -Date of Application, 21st July, 1888
Specification Accepted, 24th Aug., 1888
I, FREDERICK SIEMENS of No. 12 Queen Anne's Gate, Westminster in the County
of Middlesex, Engineer, 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 :-
The construction of steel chains has presented difficulties, as the metal of the links
cannot easily be welded, and the construction of links in such a manner as to dispense
with welding has rendered the chains too expensive for ordinary use.
This invention relates to the construction of chains with tubular links in a simple
and inexpensive manner as follows.
Two pieces of steel tube are bent each into U form and their limbs are joined so as to
make a complete link in any of the following ways. The one tube may be of larger
diameter than the other so that the limbs of the smaller can be inserted into those of
the other, or the tubes may be of equal diameter, and a limb of the one tapered at
the end to a smaller diameter to enter a limb of the other tapered to a larger
diameter, or the two sets of limbs may be brought to butt against each other
with short pieces of tube or rod inserted and extending some distance into both
of them.
The half links in each of those cases, being jointed together as spigots and faucets,
are prevented from separating by indenting them so as to make protuberances inside
the outer project into hollows formed on the inner. The half limbs may also be
connected by pieces of tube or rod with right and left threads screwed inside of
them, or pieces of tube with right and left threads screwed outside of them.
Instead of making each link in U shaped halves as above described, a single piece
of tube may be bent to form the double loop of a link, its two ends at one side of
the link being jointed together and secured as above described. In order to strengthen
the links at their bends, struts may be inserted before bending.
Figs. 1 and 2 of the accompanying drawings are longitudinal sections of tubular
links made of U shaped halves with their limbs tapered so as to enter one another in
the manner of a spigot and faucit.

page_text: Fig. 3 shews the two U shaped halves butting together with lengths of smaller
tube enclosed within the meeting limbs. Instead of the internal pieces being tubular
they may be solid pieces, as shewn in Fig. 34 and in this case these pieces may be
indented before being introduced. As shewn in Fig 3 the pieces for uniting the
halves are screwed in with right and left threads, and as shewn in Fig. 3° they are
tubular pieces screwed on outside.
Fig. 4 shews a single piece of tube bent to form the complete link with the one
limb tapered to engage in the other; and Fig. 5 shews a similar link with a piece of
smaller tube, or it might be rod, enclosed in the two meeting limbs. Fig. 6 is an
elevation of part of a chain consisting of links such as are shewn at Fig. 3. Struts &
may be inserted, as shewn in Fig. 4, to strengthen the link at its bends. In uniting
the parts, the exterior part may be heated to shrink on the interior parts.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
The herein described construction of tubular steel chains by bending lengths of
tube so as to form links.