Improvements in the Manufacture of Steel and other Metal Springs and the Fitting of them.
Year: 1896

page_text: Date of Application, 25th Nov., 1896
Complete Specification Lett. 25th Aug., 1897-Accepted, 25th Sept., 1897
Improvements in the Manufacture of Steel and other Metal Springs
and the Fitting of them.
I, ILLIUS AUGUSTUS TIMMIS of 2 Great George Street, Westminster S.W., Civil
Engineer do hereby declare the nature of this invention to be as follows:-
The objects of this invention are to make long bar springs which shall be more
sensitive than, and not have the friction of, laminated springs and at the same time
shall have less camber than laminated springs, and as a consequence cause vehicles to
run more easily and smootb'y.
With these objects in view I take an ingot of steel or other suitable metal (herein-
after called steel) and reduce it to any suitable size by hammering rolling or pressing.
This bar may be of any suitable cross section.
I then reduce it from the centre to the ends so that it is largest at the centre and
smallest at the two ends, and I make one two or more grooves in it. It then
resembles in principle the blades of two rapiers, placed, and joined, base to base.
But as the principle holds good that an arch cannot be turned on itself I prefer to
make an arch on the bottom and one on the top and also one on either side thus
leaving a centre and four webs.
There may however be different shapes in cross section used.
There is nothing so far that is patentable, but I have found that they can only be
made by special ineans and these I now describe and claim.
First I take a bar rolled to a suitable size and I press or squeeze it by powerful
rams to the required dimensions, or
Secondly I take a bar and fix it between two cam rolls and roll the bar out from
the centre to one end, or one cam roll may be used with a travelling counterpart. If
these means are employed the presses or the cam rolls are provided with recesses or
grooves of such shapes that when the rolls of one pair are in contact and the grooves
or recesses opposite each other an opening of cruciform section but of decreasing size
is formed, which is that to be imparted to the bar. The cross section may be other
than cruciforin. If a small fillet should be left at the edges it should be cut off.
Thirdly I use milling cutters to make the grooves.
Fourthly I employ a set of top and bottom rolls and also two side rolls all cam
shaped to roll in the four arches or grooves.
The ends may be left plain or inade with eyes or partially turned over.
When used as bearing springs I may fit part to carry the load and part to act as
relief springs, the latter with a slight initial load on or no load at all. This is a new
feature.
These bars when properly tempered make perfect springs.
These spring bars may be fitted side by side or over each other with suitable fittings
to hold the centre and ends of each bar.
Another mode of fitting them is to make several bars of different lengths and to
place one over or under the other like laminated springs and then I prefer to fit small
rollers on the ends.

page_text: place one over or under the other like laminated springs and then I prefer to fit smal
rollers on the ends.
The essentially new features in this invention are the means of making them by
presses, cam rolls and milling cutters, and fitting them so that when inore than one
bar is used to take the same load a part are more heavily loaded than the
remainder.
In order that my invention may be the better understood I append a drawing
which is descriptive of one of the processes herein before mentioned.
Fig. 1 is a ring or annulus, preferably of steel suitably grooved on the outside.
Cross sections of the ring at various points, G, A, B, C, D, E, F are shown on a larger
scale in Figs. 2 to 8 respectively and show the nature of the groove. Half the ring
only is shown, but it may be a complete ring or annulus. For the purposes of rolling
it is mounted and keyed on a mandrel or other suitable support so as to be rotated
about its centre. These rings work in pairs or in the same plane and are so arranged
that parts of the grooving with the same cross section always come together. They
are called cam rolls because the grooving is cam shaped.
Thus any metal passed through these rings is squeezed or pressed into a bar having
cross sections at various positions as shown in Figs. 2 to 8.
In the case of four rolls being used each ring would be grooved to a section
as indicated in the right or left half respectively of the cross section shown in
Figs. 2 to 8.
It is necessary to so gear the rolls that they always revolve at the same speed and
that same cross sections of the grooving always come together. Allowance also
has to be made in case of wear and repairs for bringing the rolls closer
together.
Instead of cutting the rolls as shown and rolling one half of the bar length at
a tine, the rolls may be cut with recesses or grooves in, thus. From G to Fas
in Fig. 1 and Figs. 2 to 8 and then continuing the grooves round the annulus as
from to G. Or commencing at F continue to G and then from G continuing
to F. Thus completing a bar in one operation, see Fig. 9 which shows the bar
finished with its proper camber, and Figs. 10 and 11, two cross sections. The same
deseription serves if four rolls are used.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:
(1) The process of manufacture of the hereinbefore described long bar springs
by means of presses, cam rolls, or milling tools, substantially as and for the
purposes herein before described."
(2) The fitting of the said long bar springs so that when more than one bar
is used to take the same load, a part are more heavily loaded than the remainder,
substantially as and for the purposes herein before described.
Dated this 5th day of At 1007