Year: 1887

page_text: Date of Application, 16th Apr., 1887.
Specification Accepted, 17th May, 1887.
I, SAMUEL HAHN, of 14 Mathienstrasse, Berlin, in the Empire of Germany, Manu-
facturer, 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 :-
This invention relates to sewing machines in which the cloth or other material to be
sewn is folded in the fashion of corrugations and fed by suitable interlocking toothed
or open wheels on to a needle with thread which is thereby caused to pierce the
material alternately from each side and thus form a running stitch.
The improvements relate more especially to the machine described in the Specifica-
tion and illustrated in the drawings of Letters Patent No. 2832 dated 17th August
1874 and are fully shown in the claim hereafter.
In the machine therein shown it has been found that owing to the direction of the
point of the needle not being in the line of the feed of material or of the shank of the
needle by which term is to be understood that straight portion of the needle which
ends with the eye-the needle was apt to be bent or broken by the unequal strain of
the cloth, or displaced from the groove in which it lies and thus rendered either
entirely useless or insufficient and unequal in its action.
Referring to the accompanying drawings which show the improved construction,
Fig. 1 illustrates the improved arrangement and combination of feed wheels, being
a section on line A B Fig. 3.
Figs. 2 and 3 are respectively end or side, and front elevations of the machine.
Fig. 4 illustrates the arrangement of the feed wheels as formerly used..
With the four feed wheels c d ab formerly employed is combined the fifth wheel e
in such a manner that the axes of e and 6 lie in a plane vertical to the feed of the
material. To enable this to be done, the wheel & is brought further forward than was
formerly the case.
It is understood that this fifth wheel may be either above or below b. The
needle k is curved as formerly and lies in a groove in the teeth of the wheels, its
point ending exactly in the plane of e band being directed perpendicular to said
plane.

page_text: The groove in which the needle k lies does not extend to the base of the teeth of
the wheels, but is only of such a depth to enable the wheels to be sufficiently approxi-
mated to secure a perfect feed of material while the needle lies snugly in the grooves,
being supported on each side by the base of the grooves without undue pressure.
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 combination of the toothed wheels bad c arranged as described with a
toothed wheel e the axis of which lies in a plane with the axis of the first of the above
set, the said plane being perpendicular to the feed of material substantially as set
forth.
2. The combination with the toothed wheels band e of the needle the point of
which is situated in the plane passing through the axes of said wheels, and is directed
perpendicular to said plane substantially as set forth.
3. In the said wheels, a groove for the reception of the needle, said groove
extending into the teeth but not to the base of the same substantially as and for the
purpose set forth.
By Herbert & Co.,
S. HAHN.
67, Strand, W.C.,
Agents to Applicant.