Improvement in the Manufacture of Forks for Hay or other Agricultural Purposes.
Year: 1887

page_text: Date of Application, 20th Jan., 1887
Complete Left, 27th Sept., 1887
Complete Accepted, 4th Nov., 1887
PROVISIONAL SPECIFICATION.
Improvement in the Manufacture of Forks for Hay or other
Agricultural Purposes.
I, CHRISTIAN ULDALL, of Copenhagen, in the Kingdom of Denmark, Manufacturer,
do hereby declare the nature of this invention to be as follows:-
This invention consists in producing forks for agricultural purposes out of flat
plates of metal, which are given a suitable shape by pressing. The tines are by
this process made tubular, and can easily be mado sufficiently strong as solid tines,
by an advantageous distribution of the material, the weight being considerably
reduced and the work simplified.
The following is a description of the process for producing two tined hay forks,
which process is also adapted for the manufacture of forks with more tines.
A piece
of metal of suitable thickness and of a broadened fork-shape is stamped from a steel
plate. This piece is then passed through two presses, or stamps with suitable matrices,
these curve up the prongs and shank so as to almost form closed tubes of the same,
these are next completely closed by bending over the sides by pressure between a
third pair of stamps.
Since, during the above processes the tines are in close proximity to each other, they
must be bent apart to the desired distance. For this purpose, the fork is now brought
over a saddle-shaped matrix and the forks are bent outward thereby and the whole
fork receives so far the shape intended for it so that there only remains for the tines
to be closed by welding, pointed and given the proper upward curvature. This
curvature is produced by further moulds or shapers. Whon the hay fork leaves these,
it is ready for being tempered, polished and provided with a handle.
1007
HERBERT & Co.,
67, Strand,
Agents.

page_text: COMPLETE SPECIFICATION.
Improvement in the Manufacture of Forks for Hay or other
Agricultural Purposes.
I, CHRISTIAN ULDALL of Copenhagen in the Kingdom of Denmark, Manufactures,
do hereby declare the nature of my invention, and in what manner the same is to be
performed, to be particularly described and ascertained, in and by the following
statement —
Figure 1 is a plan view of the blank for my improved hollow fork. Figs. 2 and 2ª
show, respectively, in plan view and in side view a partly-finished fork resting in the
lower die. Fig. 3 is a transverse sectional view of the upper and lower dies and of
the blank. Fig. 4 is a similar view showing the blank in dies giving a still further
bending to the blank. Fig. 5 is a similar view showing the edges of the blank
brought together. Fig. 6 is a plan view of dies for giving the prongs or tines of
the fork their proper lateral curve, and Fig. 7 is a longitudinal vertical sectional view
of dies giving the final curve to the prongs or tines of the fork.
Similar letters of reference indicate corresponding parts in all the figures.
My invention has relation to forks especially used for agricultural purposes, such as
hay and dung forks; and it consists, first, in the improved method of and apparatus
for manufacturing hollow pronged forks, and, second, in the improved construction of
the hollow-pronged fork produced by the method as hereinafter more fully described
and claimed.
In the accompanying drawings, the letter a indicates the portion of the blank which
is intended for the socket of the fork for the insertion of the handle, and band b
indicate the portions of the blank forming the tines or prongs. This blank, which for
a two-pronged fork is of substantially the same shape as shown in Fig. 1, is placed in
a lower die, A having a small concavity in its face corresponding in shape to the
general outline of the blank, and an upper die, A' is forced down upon the blank, as
shown in Figs. 3 and 4, the dies first used having less recess and raised portion,
respectively, than the dies used afterwards, the dies gradually bringing the edges of
the blank to curve upward and toward each other, as shown in Fig. 4. The blank is
then placed between two dies B' and B2, of which the lower one is formed with a
shallow groove corresponding in shape to the form of the pressed blank, and the upper
die is formed with a groove c, having inclined or bevelled sides, as shown in Fig. 5,
the two parts of the said groove gradually tapering toward their points, and the
inclined sides of the groove will serve to close the edges of the blank and give the
pressed and nearly finished blank the proper shape. The ends of the tines are now
welded and tapered, whereon the blank is placed into a die formed in two parts, D'and D²,
inclosing the socket and the outer sides of the prongs, and a plunger D³ of a blunt
and rounded wedge shape inserted between the prongs, spreading them and giving
them the proper lateral curve.
It now remains to give the prongs the proper curve transversely to the plane through
the socket and prongs, and this is accomplished by placing the fork between two
dies E and E, respectively formed in their faces with a groove corresponding to the
shape of the fork, having a concave and a convex-curved face, so that it may be curved

page_text: into a shape below the plane between the points of the prongs and the socket. The
fork is now so far finished that all that remains is to temper it and to polish and
finish it for the market, and it will be seen that a very light article is obtained on
account of the prongs being hollow, while these will be equally as strong and possess
comparatively greater elasticity and yielding power than the solid and heavier ones.
When forks with more than two prongs are manufactured, the dies will of course
have their respective grooves and raised parts formed to correspond to the shape of the
many-pronged blank, and as to the three pronged forks, the plunger in the die giving
the lateral spread to the prongs will be divided into 2 parts, each of them corresponding
to the space between two prongs, the entire operation and method of manufacture
being the same as with the two-prongod fork, the only difference being the difference
in the shape of the dies.
For forks with more than three tines the blank is directly to be cut out with the
full space between the tines, and consequently the use of the dies Fig. 6 may be
omitted.
In some cases say Coke-forks with a greater number of tines-the tines are not
necessarily closed entirely together, and consequently the use of the dies Fig. 5 may
be wholly or partly omitted.
The dies are here shown flat, one die being forced down upon the other; but it
follows that the dies may be formed upon rollers botween which the blanks may be fed,
in the same manner as a number of other inetallic objects are cut or formed from
rough blanks inserted between roller-dies as, for instance, links and similar objects.
Numerous other modifications may be made in the construction of the different
parts of the dies and other machinery for manufacturing the forks without departing
from the spirit of my invention, which changes all may suggest themselves during the
manufacture of the implements.
Having now particularly described and ascertained the nature of my invention, and
in what manner the same is to be performed, I declare that what I claim is :-
1. The improved method of manufacturing hollow-pronged forks, consisting in
gradually curving the edges of a flat fork-shaped blank between dies, closing the
points by welding, and then giving the fork the desired lateral and transverse curve
of the prongs, as and for the purpose shown and set forth.
2. The improved apparatus for manufacturing hollow-pronged forks, consisting of
upper and lower dies, a blunt and rounded wedge-shaped plunger, a pair of forked-
shaped dies and two dies having, respectively, a convex and a concave face, as and
for the purpose shown and set forth.
3. In an apparatus for manufacturing hollow-pronged forks, the combination of a
pair of fork-shaped dies having prongs-receiving grooves in the inner sides of its
branches and a blunt rounded wedge-shaped plunger having grooves in its sides, as
and for the purpose shown and set forth.
4. In an apparatus for manufacturing hollow-pronged forks, the combination of two
dies, one of which has a shallow groove, and the other one has a groove the sides of
which are bevelled or inclined toward each other, as and for the purpose shown and
set forth.
5. As an improved article of manufacture, a fork having tubular or hollow prongs,
as and for the purpose shown and set forth.