Improvements in the Manufacture of Springs for Animal Traps.
Year: 1889

page_text: Date of Application, 24th May, 1889-Accepted, 29th June. 1889
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Springs for Animal Traps.
I, WILLIAM HENRY TILDESLEY of 88, Walsall Street, Willenhall, Staffordshire,
Curry-comb Manufacturer, 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 has reference to the springs of those animal traps which are provided
with a pair of jaws hinged to the frame of the trap and which pass through a bow or
loop at the end of the spring so that when the jaws are released the looped end of the
spring in rising causes them to close.
Heretofore it has been customary to forge the loop or eye at the end of the spring
from a strip of wrought iron which is divided for a certain distance longitudinally and
the divided parts bowed out and welded together to form the eye, the other end being
welded on to a steel shank. This method of manufacture is comparatively expensive
as it is rather a slow process and can only be performed by skilled workmen; more-
over the said springs when so formed are liable to break where they are welded.
The object of this invention is to form the said springs from a strip of steel in a
quicker manner and without a weld or seam which I will now describe by referring to
the accompanying drawing on which Fig. 1 represents a strip of steel for forming the
spring represented in front and sectional side elevation by Fig. 3; Fig. 2 represents
the same when partly formed; Fig. 5 represents a similar spring to Fig. 3 but rather
wider and Fig. 4 shews the spring represented by Fig. 5 when partly formed; Fig. 6
represents in front elevation and Fig. 7 in side elevation a pair of tools for use in the
manufacture of the said springs as hereinafter described and Figs. 8 and 9 shew cross
sections of one of the said tools.
In carrying out my invention I take a strip of flat steel spring B as represented for
instance by Fig. 1 and then by means of suitable cutting out tools I pierce the oblong
hole a near one end thereof as shewn by Fig. 2 and also round off the extreme end 6
and cut the two side notches c¹ c². This is by preference all done at a single operation
in a cutting out press by tools of the proper shape as will be readily understood. The
metal round the oblong hole a is left of the same thickness as the metal round the
required eye or loop at the end of the finished spring. The blank represented by
Fig. 2 is then heated and the metal round the slotted hole a is bent out so that the
eye or loop a will now have the form represented by Fig. 3 and the notches e' c² will
correspond with the reduced neck at the base of the eye. This can be accomplished
by means of a wedge shaped upper tool d and suitable bed e such for instance as that
represented by Figs. 6, 7, 8 and 9. It will be seen that the lower end d' of the tool d
is tapered so that it can be inserted in the slot a in the blank represented by Fig. 2
and that the upper part of the tool as seen in cross section by Fig. 8 is of similar
shape to the required eve a of the finished spring as seen in Fig. 3. The heated
blank B is placed upon the bed e and when the tool d descends (the same being
suitably guided as in a cutting out press) the metal 62 round the slot a is bent out to
the form represented by Fig. 3. A suitable drawing off plate is provided for keeping
down the blank B when the tool d rises so as to withdraw the blank off the tool.
oval hole a in the blank B (Figs. 2 and 4) is made of such a length that the metal b³
round it will be of the same length as the metal round the finished eye thus preventing
any stretching or drawing of the metal while it is being buiged out in forming the
ye.
The
Wider springs as illustrated by Fig. 5 can be formed in a similar manner to
hat above described the metal 62 round the hole a in the blank illustrated by Fig. 4
being left at the same or about the same width as the metal round the eye in the
1

page_text: 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 :-
The process of making an animal trap spring having an eye or loop at one end,
which process consists in forming a blank by piercing and cutting a strip of steel or
other suitable metal or alloy to the form substantially as described and shewn in
Figs. 2 or 4, then heating the said blank and then whilst hot bulging out the metal
round the eye to the required form, substantially as set forth.
Dated this 23rd day of May 1889.
CHARLES BOSWORTH KETLEY,
Agent for the Applicant.