Improvements in Button-hole Sewing Machines.
Year: 1886

page_text: Improvements in Button-hole Sewing Machines.
I, ALEXANDER ANDERSON, Manager, of The Singer Manufacturing Company's
Works, Kilbowie, Dumbartonshire, do hereby declare the nature of this invention,
and in what manner the same is to be performed, (as communicated to me from
abroad by The Singer Manufacturing Company of New York, in the United States
of America, Sewing Machine Manufacturers,) to be particularly described and
ascertained in and by the following statement:-
My invention relates to certain improvements in the cutting mechanism for
button-hole sewing machines, the object of my invention being to relieve the bed
plate of the machine of the shock or jar of the striking button-hole cutter or
cutting lever. To this end I provide, beneath the bed plate of the machine, a
sustaining block which extends under the forward end of the rock-shaft by which
the cutting mechanism is operated so that the said shaft may be supported by the
said sustaining block when the cutting blow is given, thus transferring the force of
the blow to the said block and thereby relieving the bed-plate from the shock
thereof.
In the drawings figs. 1 and 2 are side views, partly in section, of sufficient of a
button-hole sewing machine to illustrate my invention, the parts being in different
positions in the two views. Fig. 3 is a detail end view, the parts therein shown
being in the same position as in fig. 1, and fig. + is a view similar to figure 3 but
with the parts in position indicated by fig. 2.
Fig. 5 is an end view of the bed-plate, partly in section, and figs. 6, 7 and 8 are
views, similar to figs. 2, 3 and 4, respectively, illustrating a modified form of my
invention.
A, denotes the bed-plate and B, a portion of the arm of a button-hole sewing
machine. C, is a rock shaft supported by centre screws passing through hangers a
depending from the bed-plate A, said shaft being connected by a link d with
a striking cutting lever D, having at its forward end a weighted head carrying a
cutting block d. The shaft C is provided at its rear end with an operating handle c
and at its forward end with a cam c³. Pivoted to ears a¹, on the bed-plate A, is an
arm or lever G, which rests on the cam c³, and to the said arm or lever is attached
the button-hole cutter g.

page_text: The cutter is in the present instance, below the bed-plate and the cutting block
above, and the cutting mechanism is operated by moving the handle c quickly
upwards from the position indicated in fig. 3 to the position indicated in fig. 4.
To relieve the bed-plate of the shock of the blows of the cutting lever, and thus
prevent the mechanism carried by the said plate from being disarranged or other-
wise injured by such shock, I provide a sustaining block F which is arranged
beneath the lifting cam ca on the rock-shaft c, or, in other words, beneath the
forward end of the said shaft. The bed-plate A is hinged at its rear side to
standards secured to the table E, and I prefer to support the front side of said
bed-plate by a post f also secured by said table. In the present instance the
standards F, f, respectively, are formed integral with the base pieces f¹, f¹, of
the said sustaining block and post. The standard f' is not clearly shown except
in figure 6 (from which the post fis omitted) but it will be understood that it is or
may be of the same form as the standard F' clearly shown in fig. 5.
On the shaft C is a small cam c', which may be merely an extension of the cam c³.
When the handle c is lifted in the operation of cutting a button-hole the cam c*,
impinging against the sustaining block F (or a cushion or plate f³ thereon) lifts
the bed plate A slightly from the post f (see fig. 2) and the force of the blow of
the cutting lever D will thus be communicated to the said block F, thereby
relieving the bed-plate from the shock of the blow.
Instead of supporting the front side of the bed-plate by the post f, as above
described, said post and also the cam c¹ may be omitted and the forward end of the
shaft C may rest directly on the block F which will thus serve as a support for
the front side of the bed-plate both when the button-hole is being cut and at other
times (see figs. 6, 7 and 8). I prefer, however, to employ the post fand cam c', as
herein before described, as with this construction there will be less friction on the
shaft C at the beginning of the movement of the latter in cutting, but I do not wish
to be understood as limiting my invention to this my preferred construction.
It will be obvious that instead of arranging the cutter g below the bed-plate
and the cutting block d¹ above the same the positions of these two parts may
be reversed.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me, I declare that what I claim is :-
1. In a button-hole sewing machine, the combination with the striking cutter
lever, the cutting block, the cutter and the rock-shaft by which the said cutter and
block are operated of a sustaining block beneath the bed-plate arranged beneath
the forward end of the said rock-shaft, whereby, when the cutter is operated, the
force of the blow will be communicated to said sustaining block and the bed plate
be relieved of the shock, as set forth.
2. In a button-bole sewing machine, the combination with the hinged bed-plate,
a post for supporting the front side thereof, a striking cutter lever, a cutting block,
a cutter and rock shaft for operating said cutter and block, of a sustaining block
beneath the said bed-plate, and a cam on said rock-shaft adapted to impinge
against said sustaining block to lift the front side of the bed-plate from the said
post when the cutter is operated, substantially as and for the purpose set forth.
Dated this First day of September 1886.